I NEED HELP ASAP
191 of the 288 high school students surveyed at a local school said they went outside more during school hours as elementary school students than they do now as high school students. Calculate the Margin of Error, rounded to the nearest tenth of a percent. Is it reasonable that the state education department claims the percentage for the entire state is 73%? Justify your answer.
Answers
Answer:
It is not reasonable that the state education department claims the percentage for the entire state is 73%.
Step-by-step explanation:
We are given that 191 of the 288 high school students surveyed at a local school said they went outside more during school hours as elementary school students than they do now as high school students.
Firstly, the pivotal quantity for finding the confidence interval for the population proportion is given by;
P.Q. = [tex]\frac{\hat p-p}{\sqrt{\frac{\hat p(1-\hat p)}{n} } }[/tex] ~ N(0,1)
where, [tex]\hat p[/tex] = sample proportion of high school students who went outside more during school hours as elementary school students than they do now as high school students = [tex]\frac{191}{288}[/tex] = 0.66
n = sample of high school students = 288
p = population percentage for the entire state
Here for constructing a 90% confidence interval we have used a One-sample z-test for proportions.
The margin of error is given by;
M.E. = [tex]2 \times \sqrt{\frac{\hat p(1-\hat p)}{n} }[/tex]
= [tex]2 \times \sqrt{\frac{0.66(1-0.66)}{288} }[/tex]
M.E. = 0.056 or 5.6%
So, the confidence interval so formed = [tex]\hat p \pm \text{Margin of error}[/tex]
= [[tex]0.66 - 0.056 , 0.66 + 0.056[/tex]]
= [0.604, 0.716]
Since the above interval does not include 0.73 or the population proportion of 73% falls outside the above interval. So, it is not reasonable that the state education department claims the percentage for the entire state is 73%.
Related Questions
Angle A corresponds to angle____
B
C
E
D
none of the above
Answers
Explanation:
There is no angle corresponding to angle A
Answer:
Angle E.
Step-by-step explanation:
Hope this helps!
A machine used to fill gallon-sized paint cans is regulated so that the amount of paint dispensed has a mean of ounces and a standard deviation of ounce. You randomly select cans and carefully measure the contents. The sample mean of the cans is ounces. Does the machine need to be reset? Explain your reasoning. ▼ Yes No , it is ▼ very unlikely likely that you would have randomly sampled cans with a mean equal to ounces, because it ▼ lies does not lie within the range of a usual event, namely within ▼ 1 standard deviation 2 standard deviations 3 standard deviations of the mean of the sample means.
Answers
Complete question is;
A machine used to fill gallon-sized paint cans is regulated so that the amount of paint dispensed has a mean of 128 ounces and a standard deviation of 0.20 ounce. You randomly select 35 cans and carefully measure the contents. The sample mean of the cans is 127.9 ounces. Does the machine need to be? reset? Explain your reasoning.
(yes/no)?, it is (very unlikely/ likely) that you would have randomly sampled 35 cans with a mean equal to 127.9 ?ounces, because it (lies/ does not lie) within the range of a usual? event, namely within (1 standard deviation, 2 standard deviations 3 standard deviations) of the mean of the sample means.
Answer:
Yes, we should reset the machine because it is unusual to have a mean equal to 127.9 from a random sample of 35 as the mean of 127.9 doesn't fall within range of a usual event with 2 standard deviations of the mean of the sample means.
Step-by-step explanation:
We are given;
Mean: μ = 128
Standard deviation; σ = 0.2
n = 35
Now, formula for standard error of mean is given as;
se = σ/√n
se = 0.2/√35
se = 0.0338
Normally, the range of values should be within 2 standard deviations of mean. In this case, normal range of values will be;
μ ± 2se = 128 ± 0.0338
This gives; 127.9662, 128.0338
So, Yes, we should reset the machine because it is unusual to have a mean equal to 127.9 from a random sample of 35 as the mean of 127.9 doesn't fall within range of a usual event with 2 standard deviations of the mean of the sample means.
If c o v (x comma space y )space equals space 1260, s subscript x squared equals 1600, and s subscript y squared equals 1225 , then the coefficient of determination is:
Answers
Complete Question
The complete question is shown on the first uploaded image
Answer:
The coefficient is [tex]r =0.81[/tex]
Step-by-step explanation:
From the question we are told that
[tex]cov(x, y )= 1260[/tex]
[tex]s_x^2 = 1600[/tex]
[tex]s_y^2 = 1225[/tex]
Generally the coefficient of determination is mathematically represented as
[tex]r = [ \frac{cov(x,y)}{ \sqrt{s_x^2} * \sqrt{s_y^2} } ]^2[/tex]
substituting values
[tex]r = [ \frac{ 1260}{ \sqrt{1600} * \sqrt{1225} } ]^2[/tex]
[tex]r =0.81[/tex]
Arbitron Media Research Inc. conducted a study of the iPod listening habits of men and women. One facet of the study involved the mean listening time. It was discovered that the mean listening time for a sample of 13 men was 35 minutes per day. The standard deviation was 8 minutes per day. The mean listening time for a sample of 11 women was also 35 minutes, but the standard deviation of the sample was 18 minutes. Use a two-tailed test and at 0.10 significance level, can we conclude that there is a difference in the variation in the listening times for men and women?
Answers
Answer:
Since the critical f-value of the test statistic is less than the f value of 2.9130, we will fail to reject the null hypothesis and conclude that there's no sufficient evidence to support the claim that there is a difference in the variation in the listening times for men and women
Step-by-step explanation:
We are given;
Sample size for men; n1 = 13
Sample size for women; n2 = 11
standard deviation for men; s1 = 8 minutes
Standard deviation for women; s2 = 18 minutes.
Significance level; α = 0.1
Let's state the hypothesis;
Null hypothesis;H0: (μ1)² = (μ2)²
Alternative hypothesis;Ha: (μ1)² ≠ (μ2)²
The value of the test statistic would be;
F = (s1)²/(s2)²
F = 8²/18² = 0.1975
Now, degree of freedom for n1 is;
DF1 = n1 - 1
DF1 = 13 - 1
DF1 = 12
Also, degree of freedom for n2 is;
DF2 = 11 - 1
DF2 = 10
Now, since it's two tailed, we will make use of α/2 for the F-distribution table.
Thus, α/2 = 0.1/2 = 0.05
So,from the f-table attached, at df1 = 12 and df2 = 10,the F-Critical value is;
F_α/2 = 2.9130
Since,the critical f-value of the test statistic is less than 2.9130, we will fail to reject the null hypothesis and conclude that there's no sufficient evidence to support the claim that there is a difference in the variation in the listening times for men and women
Identify the decimals labeled with the letters A, B, and C on the scale below. Letter A represents the decimal Letter B represents the decimal Letter C represents the decimal
Answers
[tex]10[/tex] divisions between $15.59$ and $15.6$ so each division is $\frac{15.60-15.59}{10}=0.001$
A is 5 division from $15.59$, so, A is $15.59+5\times 0.001=15.595$
similarly, C is 4 division behind $15.59$ so it is $15.590-4\times0.001=15.586$
and B is $15.601$
A state lottery randomly chooses balls numbered from through without replacement. You choose numbers and purchase a lottery ticket. The random variable represents the number of matches on your ticket to the numbers drawn in the lottery. Determine whether this experiment is binomial. If so, identify a success, specify the values n, p, and q and list the possible values of the random variable x. Is the experiment binomial? A. Yes, there are a fixed number of trials and the trials are independent of each other. B. No, because the probability of success is different for each trial. C. No, there are more than two outcomes for each trial. D. Yes, the probability of success is the same for each trial.
Answers
Answer:
B. No, because the probability of success is different for each trial.
The experiment is not binomial.
Step-by-step explanation:
The trials are not independent because they are chosen without replacement.
There are successes and failures but the trials are dependent.
So it is not binomial.
When the balls are not replaced the probability of success becomes different for each ball.
Suppose we have 10 balls and we pick out 1 so the p1 = 1/10
but when we again pick out another without replacement the p2= 1/9
This explains why it is not binomial. In binomial the n is fixed.
In a survey of 15000 students of different schools, 40% of them were found to have tuition before the see examination. Among them 50% studied only mathematics ,30% only science and 10% studied others subject. how many student studied mathematics as well as science.
Answers
Answer: 600 students.
Step-by-step explanation:
Ok, we start with 15,000 students.
40% of them had tuition, so the actual number of them that had tuition is:
15,000*0.40 = 6,000.
Now we want to find the number of students that studied math and science.
50% only studied math,
30% only studied science
10% studied other subjects.
So 50% + 30% + 10% did NOT studied both math and science
90% is the percentage that did not study math and mathematics as well as science, then the other 10% did.
Then, out of the 6,000 students that had tuition, 10% studied math and science, the total number is:
6,000*0.10 = 600
The numbers of words defined on randomly selected pages from a dictionary are shown below. Find the mean, median, mode of the listed numbers. 72 58 62 38 44 66 42 49 76 52 What is the mean? Select the correct choice below and ,if necessary ,fill in the answer box within your choice.(around to one decimal place as needed)
Answers
Answer:
72 58 62 38 44 66 42 49 76 52 ( arrange it!)
38 42 44 49 52 58 62 66 72 76 (done!)
Median: Find the number in the middle after we arranged, so the answer is (52+58)/2= 110/2 = 55
Mode : None (there is no number appear more than other number)
Mean = (38+42+44+49+52+58+62+66+72+76)/10
=559/100
=5,5
Hope it helps ^°^
The Freeman family is barbecuing veggie burgers, corn cobs, and mushroom caps in their local park. If 3 8 of the items barbecued are veggie burgers, and 1 3 of the items barbecued are corn cobs, what fraction of barbecued items are mushroom caps?
Answers
Answer:
The answer is below
Step-by-step explanation:
The Freeman family barbecued veggie burgers, corn cobs, and mushroom caps. 3/8 of the items barbecued are veggie burgers, and 1/3 of the items barbecued are corn cobs.
Let the total number of berbecued items be x. Therefore:
x = barbecued veggie burgers + barbecued corn cobs + barbecued mushroom caps
Barbecued veggie burgers = (3/8)x, barbecued corn cobs = (1/3)x, Let barbecued mushroom caps be y
Substituting:
x = (3/8)x + (1/3)x + y
Multiply through by 24
24x = 9x + 8x + 24y
24x = 17x + 24y
24y = 24x - 17x
24y = 7x
y = (7/24)x
barbecued mushroom caps = (7/24) of items
7/24 of the items barbecued are mushroom caps
Using fractions, it is found that the fraction of barbecued items that are mushroom caps is of [tex]\frac{7}{24}[/tex].
---------------------------
The total proportion of all products is 100% = 1.The fraction corresponding to veggie burgers is [tex]\frac{3}{8}[/tex].The fraction corresponding to corn cobs is [tex]\frac{1}{3}[/tex].The fraction corresponding to mushroom caps is x.---------------------------
Thus:
[tex]\frac{3}{8} + \frac{1}{3} + x = 1[/tex]
Solving for x, we find the fraction of mushroom caps.The least common multiple of 3 and 8 is 24.Then:
[tex]\frac{3\times3 + 8\times1 + 24x}{24} = 1[/tex]
[tex]\frac{17 + 24x}{24} = 1[/tex]
[tex]17 + 24x = 24[/tex]
[tex]24x = 7[/tex]
[tex]x = \frac{7}{24}[/tex]
The fraction of barbecued items that are mushroom caps is of [tex]\frac{7}{24}[/tex].
A similar problem is given at https://brainly.com/question/4231000
What is 28% of 58?
Hhhhhhh
Answers
Answer:
16.24
Step-by-step explanation:
of means multiply
28% * 58
Change to decimal form
.28 * 58
16.24
Answer:
[tex]\Large \boxed{\mathrm{16.24}}[/tex]
Step-by-step explanation:
[tex]28\% \times 58[/tex]
[tex]\displaystyle \sf Apply \ percentage \ rule : a\%=\frac{a}{100}[/tex]
[tex]\displaystyle \frac{28}{100} \times 58[/tex]
[tex]\sf Multiply.[/tex]
[tex]\displaystyle \frac{1624}{100} =16.24[/tex]
About 10% of the human population is left-handed. Suppose a researcher speculates that artists are more likely to be left-handed than other people in the general population. The researcher surveys 200 artists and finds that 26 of them are left-handed.Required:a. Define the parameter of interest and give the null value.b. State the researcher's null and alternative hypotheses.c. What proportion of the sample of artists is left-handed?d. To calculate a p-value for the hypothesis test, what probability should the researcher calculate? Make your answer specific to this situation.
Answers
Answer:
Given the information in the question;
a) The parameter of interest is the population of artists who are left-handed and its is 10% = (10/1000 = 0.10
b) The Null hypothesis and alternative hypothesis are;
H₀ : p = 0.10
H₁ : p > 0.10
c) The sample proportion is calculated as:
p = number of left handed artist / sample size
p = 26 / 200
p = 0.13
d) To find the p-value, The researcher should calculate the probability that the sample proportion would be 0.13 or larger for a sample of size 200 if the population proportion is actually 0.10.
What is the absolute value of the difference in the x-values between (1,7) and (3,11)
Answers
Answer:
2.
Step-by-step explanation:
The first numbers in the ordered pairs are the x values;
Difference = 1 - 3 = -1
The absolute value is 2.
An absolute value of |x| {modulus of x} is the value of a real number x. The absolute value of the difference in the x-values between (1,7) and (3,11) is 2.
What is Absolute Value?An absolute value of |x| {modulus of x} is the value of a real number x, the value we get is always a non-negative number, for example, |-5| will give 5, and also, |5| will give 5 as well.
Given the two coordinates (1, 7) and (3, 11) this can be written as,
(x₁ , y₁) = (1, 7)
(x₂ , y₂) = (3, 11)
Now, the absolute value of the difference in the x-values between (1,7) and (3,11) can be written as,
Absolute difference = |x₁ - x₂|
= |1 - 3|
= |-2|
= 2
Hence, the absolute value of the difference in the x-values between (1,7) and (3,11) is 2.
Learn more about Absolute value here:
https://brainly.com/question/1301718
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What is the midpoint of the segment below?
A.
(0, 0)
B.
(-1, 1)
C.
(0.5, 0.5)
D.
(0.5, -0.5)
Answers
Answer:
B(-1,1) so you can find that when you calculation for the basic principles
Determine whether the samples are independent or dependent. A data set included the daily number of words spoken by 210 randomly selected women and 210 randomly selected men.a. The samples are independent because there is a natural pairing between the two samples. b. The samples are dependent because there is a natural pairing between the two samples. c. The samples are dependent because there is not a natural pairing between the two samples. d. The samples are independent because there is not a natural pairing between the two samples.
Answers
Answer:
The correct answer is:
The samples are independent because there is not a natural pairing between the two samples. (d.)
Step-by-step explanation:
Paired samples or dependent samples are samples in which natural matching or coupling occur, thus creating a data set where data from one sample is uniquely paired to another sample because they are from related groups. Examples are: pre-test/post-test data gotten before and after an intervention, samples from siblings, twins, couples etc.
On the other hand, independent or unpaired samples are those data sets that are gotten from unrelated groups, these type of samples are gotten by matching randomly sampling two unrelated groups without first matching the subjects. In our example, the sample from randomly selected women and men are not paired and unrelated, hence they are independent samples.
The samples are independent because there is not a natural pairing between the two samples. Hence, option (D) is correct.
Let us understand both the events in a systematic manner to answer this question.
Independent Events:
The simple way to understand the events, If the events are not related to each other, then the events are independent of each other. If one event is dependent on another then it is not an independent event.
Example:
Event 1: Toss a coin.
Event 2: Roll a die.
Both the events are independent of each other.
Dependent Events:
The simple way to understand the events, If the events are related to each other, then the events are independent of each other. If one event is dependent on another then it is not an independent event.
Example:
Event 1: Toss a coin.
Event 2: If head appears then roll a die.
Both the events are dependent on each other.
Thus, the samples are independent because there is not a natural pairing between the two samples.
To know more about it, please refer to the link:
https://brainly.com/question/12138721
In a cumulative relative frequency curve, the interval with the highest proportion of measurements is the interval with the:_______
a. flattest slope.
b. steepest slope
c. backward slope.
d. negative slope.
Answers
Answer:
b. steepest slope
Step-by-step explanation:
The cumulative relative frequency curve also known as Ogive is used for reading the median, upper quartile, lower quartile from the curve and calculating the semi-interquartile range when needed.
From the cumulative relative frequency curve, the interval with the highest proportion of measurements is the interval with the steepest slope. This is because the cumulative relative frequency curve always have a positive slope, and given that the interval has the highest proportion, then the slope will be steepest.
PART A: Suppose at another time you would like to use the same pancake recipe. You have plenty of all the ingredients except that you only have 3 eggs. Convert the recipe to use exactly 3 eggs. Blueberry Pancakes Recipe, makes 6 servings 2 cups flour 2 tablespoons baking powder 1 teaspoon salt 2 eggs 1 1/2 cups milk 1 1/4 cups blueberries Convert the recipe to use exactly 3 eggs. Hint: You may want to make use of the conversion factor 3/2. PART B: Suppose you would like to make pancakes according to the given recipe: Blueberry Pancakes Recipe, makes 6 servings 2 cups flour 2 tablespoons baking powder 1 teaspoon salt 2 eggs 1 1/2 cups milk 1 1/4 cups blueberries Convert the amount of each ingredient of the recipe to make 15 servings. Round any decimal answers to two places. Hint: You may want to make use of the conversion factor 15/6.
Answers
Answer:
see the attachment
Step-by-step explanation:
The repetitive scaling is best handled by a spreadsheet.
Part A
We know the scale factor is 3/2, so we can multiply the number of servings and everything else by 3/2. The scaled recipe will make 9 servings.
__
Part B
Since 15 = 6 + 9, we could arrive at this recipe by adding the Part A recipe to the original recipe. Instead, our spreadsheet uses the suggested 15/6 multiplier.
The formula used is shown in the spreadsheet attachment. It is filled to the right and down to cover all of the recipes and ingredients.
The arc length apothem shown below is 15 feet. Part 1) State the equation that relates arc length to central angle. Part 2) Find the angle apothem in radians. Part 3) Convert your answer from Part 2 to degrees and write it to the nearest hundredth of a degree
Answers
Answer:
ans right down there
Step-by-step explanation:
Here,Part 1
if the circle has a radius r so,
15 = r theta
here, theta is in radian.
Part 2
[tex]theta = \frac{15}{6} = 2.5[/tex]
part 3
[tex]theta = \frac{2.5 \times 180}{\pi} [/tex]
or theta =
143.2394487827058021919953870352629258310136811664108038729006
In December 2004, a report based on the National Survey on Drug Use and Health estimated that 20% of all Americans aged 16 to 20 drove under the influence of drugs or alcohol in the previous year. We would like to update this information by calculating a 98% confidence interval. How large a sample is necessary in order for the bound on the error of estimation to be 0.04?
Answers
Answer:
542
Step-by-step explanation:
We are required to find the sample size at 98% confidence interval in this question
E = 0.04
P* = 20% = 0.20
n = p* x (1-p)(Zα/2÷E)²
α = 1 - 0.98
= 0.02
To get Critical value
= 0.02/2 = 0.01
The critical value at 0.01 is 2.33
Inserting values into formula:
O.2 x 0.8(2.33/0.04)²
= 0.8 x 0.2 x 58.25²
= 542.89
The value of n must be an integer therefore the answer is 542.
If each interior angle of a regular polygon measures 160°, how many sides does it have?
Answers
Answer:
18
Step-by-step explanation:
Each exterior angle is the supplement of the adjacent interior angle, so is ...
180° -160° = 20°
The total of all n of these exterior angles is 360°, so we have ...
n(20°) = 360°
n = 18 . . . . . . . . . divide by 20°
The polygon is an 18-gon. It has 18 sides.
Answer:
18 Sides
Step-by-step explanation:
Each interior angle = 160°
Each exterior angle = 180° - 160° = 20°
The sum of the exterior angles = 360°
Hence the number of exterior angles =360°/20°
= 18
The polygon has 18 sides (since it has 18 exterior angles).
Hope this helps.
Please mark me as Brainliest.
Given the following three points, find by hand the quadratic function they represent.
(0,6), (2, 16), (3, 33)
(1 point)
f(x) = 4x2 + 3x + 6
f(x) = -42? +212 + 6
f(x) = -472 – 3r +6
f(1) = 4x2 – 3x + 6
Answers
let the function be [tex]y=ax^2+bx+c[/tex]
put $x=0, \, y=6$ , to get $c=6$
put $x=2, \, y=16$ , $16=4a+2b+6\implies 2a+b=5$
put $x=3, \, y=33$ , $33=9a+3b+6\implies 3a+b=9$
subtract the two equation, to get $a=4$
now substitute $a$ in first equation, to get $b=5-2\cdot4=-3$
so, $f(x)=4x^2-3x+6$
Evaluate b h for b = 12 and h = 2 . Type a numerical answer in the space provided. If necessary, use the / key to represent a fraction bar. Do not type spaces in your answer.
Answers
Answer:63
Step-by-step explanation:
one of these marbles is picked at random. what is the probability that a blue marble is picked?
A.1/3
B.2/5
C.1/2
D.1/4
Answers
Answer:
1/3
Step-by-step explanation:
there are twelve marbles total. there are 4 blue marbles.
4/12 = 1/3
In the figure, ∆BAT ≅ ∆CAT. Which statement is not true by CPCTC? ∠BTA ≅ ∠CTA ∠BAT ≅ ∠CAT
Answers
Answer:
The two choices are true by CPCTC. Are there other choices that were not posted?
4 Points] Under the HMM generative model, what is p(z1 = z2 = z3), the probability that the same die is used for the first three rolls? b. [4 Points] Suppose that we observe the first two rolls. What is p(z1 = 1 | x1 = 2, x2 = 4), the probability that the casino used the fair die in the first roll?
Answers
Answer:
Step-by-step explanation:
We first examine a simple hidden Markov model (HMM). We observe a sequence of rolls of a four-sided die at an "occasionally dishonest casino", where at time t the observed outcome x_t Element {1, 2, 3, 4}. At each of these times, the casino can be in one of two states z_t Element {1, 2}. When z_t = 1 the casino uses a fair die, while when z_t = 2 the die is biased so that rolling a 1 is more likely. In particular: p (x_t = 1 | z_t = 1) = p (x_t = 2 | z_t = 1) = p (x_t = 3 | z_t = 2) = p (x_t = 4 | z_t = 1) = 0.25, p (X_t = 1 | z_t = 2) = 0.7, p (X_t = 2 | z_t = 2) = p (X_t = 3 | z_t = 2) = p (X_t = 4 | z_t = 2) = 0.1. Assume that the casino has an equal probability of starting in either state at time t = 1, so that p (z1 = 1) = p (z1 = 2) = 0.5. The casino usually uses the same die for multiple iterations, but occasionally switches states according to the following probabilities: p (z_t + 1 = 1 | z_t = 1) = 0.8, p (z_t = 2) = 0.9. The other transition probabilities you will need are the complements of these. a. Under the HMM generative model, what is p (z1 = z2 = z3), the probability that the same die is used for the first three rolls? b. Suppose that we observe the first two rolls. What is p (z1 = 1 | x1 = 2, x2 = 4), the probability that the casino used the fair die in the first roll? c. Using the backward algorithm, compute the probability that we observe the sequence x1 = 2, x2 = 3, x3 = 3, x4 = 3 and x5 = 1. Show your work (i.e., show each of your belief for based on time). Consider the final distribution at time t = 6 for both p (z_t = 1) = p (z_t = 2) = 1.
ANSWER:
Let say we have that the first state of the die is state 1. Therefore the probability of this is p(z1=1)=0.5.
Also the probability that the same die is used(i.e. casino would be in the same state) is p(z2=1|z1=1)=0.8.
Again, suppose the first state of the die is state 2. So, p(z1=2)=0.5 and p(z2=2|z1=2)=0.9.
Other transition probabilities can be written as
p(zt+1=2|zt=1)=1-p(zt+1=1|zt=1)=.2
p(zt+1=1|zt=2)=1-p(zt+1=2|zt=2)=.1
p(z3=1|z1=1) = [p(z3=1|z2=2)*p(z2=2|z1=1)]+[p(z3=1|z2=1)*p(z2=1|z1=1)] = 0.1*0.2+0.8*0.8 = 0.66
p(z3=2|z1=2) = [p(z3=2|z2=2)*p(z2=2|z1=2)]+[p(z3=2|z2=1)*p(z2=1|z1=2)] = 0.9*0.9+0.2*0.1 = 0.83
With this, the total probability that the same die is used for the first three rolls (i.e. casino would be in the same state) is given thus;
{p(z1=1)*p(z3=1|z1=1)}*{p(z1=2)*p(z3=2|z1=2)}
= 0.5*0.66+0.5*0.83 = 0.745
Prob = 0.745
How do you compress this?
Answers
[tex]\displaystyle\\(a+b)^n\\T_{r+1}=\binom{n}{r}a^{n-r}b^r\\\\\\(x+2)^7\\a=2x\\b=3\\r+1=4\Rightarrow r=3\\n=5\\T_4=\binom{5}{3}\cdot (2x)^{5-3}\cdot3^3\\T_4=\dfrac{5!}{3!2!}\cdot 4x^2\cdot27\\T_4=\dfrac{4\cdot5}{2}\cdot 4x^2\cdot27\\\\T_4=1080x^2[/tex]
Next, the students at the Pearson Cooking Academy are assigned a take-home written exam to assess their knowledge of all things culinary. Historically, students scores on this exam had a N(68, 36) distribution. However, these days, there is an company called Charred Egg that offers to help students on tasks whether or not the exercises are for homework or for exams. In a cohort of 19 students, what is the probability that their average score will be at least 70?
Answers
Answer:
The probability is [tex]P( \= X \ge 70 ) = 0.07311[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 68[/tex]
The standard deviation is [tex]\sigma = \sqrt{36} = 6[/tex]
The sample size is [tex]n = 19[/tex]
Generally the standard error of the mean is mathematically represented as
[tex]\sigma_{\= x } = \frac{\sigma }{\sqrt{n} }[/tex]
=> [tex]\sigma_{\= x } = \frac{6 }{\sqrt{19} }[/tex]
=> [tex]\sigma_{\= x } = 1.3765[/tex]
Generally the probability that their average score will be at least 70 is mathematically represented as
[tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - P(\frac{ \= X - \mu }{\sigma_{\= x}} < \frac{70 - 68}{ 1.3765} )[/tex]
Generally [tex]\frac{ \= X - \mu }{\sigma_{\= x}} = z(The \ z-score \ of \ \= X )[/tex]
So
[tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - P(Z <1.453 )[/tex]
From the z-table
[tex]P(Z <1.453 ) = 0.92689[/tex]
=> [tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 1 - 0.92689[/tex]
=> [tex]P( \= X \ge 70 ) = 1 - P( \= X < 70 ) = 0.07311[/tex]
=> [tex]P( \= X \ge 70 ) = 0.07311[/tex]
As you wake up to get your day started, you decide to make muffins for breakfast. The recipe you are
using makes 2 dozen muffins and calls for 3 cups of flour and 1 cup of sugar. You decide to only make
18 muffins. How many cups of flour and sugar will you need for your recipe?
The above problem can easily be solved using a proportion. Show your work
Answers
Answer:
4 cups of flour is needed and 4/3 cups of sugar
Step-by-step explanation:
Given
2 dozen Muffins; 3 cups of flour and 1 cup of sugar
Required
Determine the cups of flour if 18 muffins is used
First, we have to determine the proportion of the number of muffins used previously and now;
Represent this with p;
[tex]p = \frac{2\ dozen}{18}[/tex]
[tex]p = \frac{2 * 12}{18}[/tex]
[tex]p = \frac{24}{18}[/tex]
[tex]p = \frac{4}{3}[/tex]
Multiply this to the previous cups of flours and sugars;
Cups of flour = p * previous cups of flour
[tex]Cups\ of\ flour = \frac{4}{3} * 3[/tex]
[tex]Cups\ of\ flour = 4[/tex]
Cups of Sugar = p * previous cups of sugar
[tex]Cups\ of\ sugar= \frac{4}{3} * 1[/tex]
[tex]Cups\ of\ sugar= \frac{4}{3}[/tex]
Hence, 4 cups of flour is needed and 4/3 cups of sugar
) A jar contains 4 white balls and 6 black balls. A ball is chosen at random, and its color noted. The ball is then replaced, along with 3 more balls of the same color. Then, another ball is drawn at random from the jar. (a) Find the chance that the second ball drawn is white. (b) Given that the second ball drawn is white, what is the probability that the first ball drawn is black
Answers
Answer:
The answer is "[tex]\bold{\frac{2}{5}\ \ and \ \ \frac{6}{13}}[/tex]".
Step-by-step explanation:
You have 4/10 opportunities to choose a white ball, and there'll be 7 white balls and 6 black balls out of 13, and so the second time they choose a white one is 7/13, as well as the second time they choose a black, 6/13. people will also have a 4/10 chance.
There are 6/10 chances which users pick its black ball and 4 white balls would still be picked, but 9 black balls and out 13 balls and thus, its second and third time you select the white one is 4/13 but you are likely to pick a black for the second time is 9/13.
Taking the diagram of the next tree. The very first draw is marked with a and the second draw is marked with b.
[tex]\to P(a) = \frac{4}{10}\ \ \ \ \ \ \ \ \ P(b) = \frac{6}{10}\\\\\to P(\frac{a2}{a1}) = \frac{7}{13} \ \ \ \ \ \ \ \ \ \ P(\frac{a}{b}) = \frac{4}{13}\\\\\to P(\frac{b2}{a1}) = \frac{6}{13} \ \ \ \ \ \ \ \ \ \ P(\frac{b2}{b1}) = \frac{9}{13}[/tex]
Calculating the second drawn ball is white:
[tex]\to P(b2)=P(a)P(\frac{a2}{b1})+P(b)P(\frac{a}{b})\\[/tex]
[tex]=\frac{4}{10}\frac{7}{13}+\frac{6}{10}\frac{4}{13}\\\\=\frac{28}{130}+\frac{24}{130}\\\\=\frac{28+24}{130}\\\\=\frac{52}{130}\\\\=\frac{2}{5}\\\\[/tex]
In point b:
[tex]\to P(\frac{b}{a1})= \frac{P(B)P(\frac{a}{b})}{P(a)P(\frac{a2}{b1})+P(b)P(\frac{a}{b})\\}[/tex]
[tex]=\frac{\frac{6}{10} \frac{4}{13}}{\frac{52}{130}}\\\\=\frac{\frac{24}{130}}{\frac{52}{130}}\\\\=\frac{24}{130} \times \frac{130}{52}\\\\=\frac{24}{52}\\\\=\frac{6}{13}\\[/tex]
22/25of a number is what percentage of that number?
Answers
Answer:
88%.
Step-by-step explanation:
Multiply the fraction by 100:
(22/25) * 100
= 22 * 4
= 88%.
The size of the left upper chamber of the heart is one measure of cardiovascular health. When the upper left chamber is enlarged, the risk of heart problems is increased. A paper described a study in which the left atrial size was measured for a large number of children ages 5 to 15 years. Based on this data, the authors conclude that for healthy children, left atrial diameter was approximately normally distributed with a mean of 26.5 mm and a standard deviation of 4.8 mm.
Required:
a. Approximately what proportion of healthy children has left atrial diameters less than 24 mm?
b. Approximately what proportion of healthy children has left atrial diameters greater than 32 mm?
c. Approximately what proportion of healthy children has left atrial diameters between 25 and 30 mm?
d. For healthy children, what is the value for which only about 20% have a larger left atrial diameter?
Answers
Answer:
a) P [ X < 24 mm ] = 0,3015 or P [ X < 24 mm ] = 30,15 %
b) P [ X > 32 mm ] = 0,1251 or P [ X > 32 mm ] = 12,51 %
c) P [ 25 < X < 30 ] = 0,4964 or P [ 25 < X < 30 ] = 49,64 %
d) z(s) = 0,84
Step-by-step explanation:
Normal Distribution N ( μ₀ ; σ ) is N ( 26,5 ; 4,8 )
a) P [ X < 24 mm ] = ( X - μ₀ ) / σ
P [ X < 24 mm ] = (24 - 26,5)/ 4,8 = - 0,5208 ≈ - 0,52
P [ X < 24 mm ] = - 0,52
And from z-table we find area for z score
P [ X < 24 mm ] = 0,3015 or P [ X < 24 mm ] = 30,15 %
b)P [ X > 32 mm ] = 1 - P [ X < 32 mm ]
P [ X < 32 mm ] = ( 32 - 26,5 ) / 4,8
P [ X < 32 mm ] = 5,5/4,8 = 1,1458 ≈ 1,15
P [ X < 32 mm ] = 1,15
And from z-table we get
P [ X < 32 mm ] = 0,8749
Then:
P [ X > 32 mm ] = 1 - 0,8749
P [ X > 32 mm ] = 0,1251 or P [ X > 32 mm ] = 12,51 %
c) P [ 25 < X < 30 ] = P [ X < 30 ] - P [ X < 25 ]
P [ X < 30 ] = 30 - 26,5 / 4,8 = 0,73
From z-table P [ X < 30 ] = 0,7673
P [ X < 25 ] = 25 - 26,5 / 4,8 = - 0,3125 ≈ - 0,31
From z-table P [ X < 25 ] = 0,2709
Then
P [ 25 < X < 30 ] = 0,7673 - 0,2709
P [ 25 < X < 30 ] = 0,4964 or P [ 25 < X < 30 ] = 49,64 %
d) If 20 %
z- score for 20% is from z-table
z(s) = 0,84
