Answer5
Step-by-step explanation:
Preeti and Shikha have bookshelves of the same size. Preeti’s shelf is 56 full of books and Shikha’s shelf is 35 full. Whose bookshelf is more full and by how much?
Answer:
Step-by-step explanation:
No of books in Preeti's shelf = 56
No of books in Shikha's shelf = 35
56 > 35
∴ Preeti's shelf is more full by 21 books
as 56 - 35 = 21
Hope this helps
plz mark as brainliest!!!
Which set of values could be the side lengths of a 30-60-90 triangle?
O A. {6,613, 12)
O B. {6, 12, 12.3}
O C. {6,6.12, 12}
O D. {6, 12, 12/3)
Answer:
I think :
c is 30 triangle
b is 60 triangle
d is 90 triangle
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?
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.
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
[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 $15.601$
Angle A corresponds to angle____
B
C
E
D
none of the above
Answer:
Angle E.
Step-by-step explanation:
Hope this helps!
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.
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
295 feet = _____ meters ?
Answer:
Hello! I hope I am correct!
Step-by-step explanation:
295 feet will equal to 89.916 meters.
Steps in order to solve this problem:
First you have to multiply the length in feet by 0.3048.
295x 0.3048 or 295* 0.3048
(295 feet is equivalent to 89.916 meters!)
Will equal 89.916 meters.
Therefore, 295 feet = 89.916 meter
Hope this helps!
Brainliest would be appreciated!
By:BrainlyAnime
(Picture attached)
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
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
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?
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
Select the correct answer -1/4(12x+8) is less than it equal to -2x+11
Answer:
x ≤ [tex]\frac{9}{5}[/tex]
Step-by-step explanation:
Given
[tex]\frac{1}{4}[/tex](12x + 8) ≤ - 2x + 11 ← distribute parenthesis on left side
3x + 2 ≤ - 2x + 11 ( add 2x to both sides )
5x + 2 ≤ 11 ( subtract 2 from both sides )
5x ≤ 9 ( divide both sides by 5 )
x ≤ [tex]\frac{9}{5}[/tex]
-¼(12x+8) ≤ -2x+11
• Divide by 44X-¼(12x+8) ≤-2x+11
= -12x + 8 ≤ -2x + 11
• Group like terms-12x + 2x ≤ 11 - 8
= -10x/10 ≤ 3/-10
x≤ 3/-10The 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?
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
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.
Answer:63
Step-by-step explanation:
Find the missing side of the triangle. A. 321−−−√ yd B. 221−−−√ yd C. 338−−√ yd D. 21−−√ yd
Answer:
[tex] x = \sqrt{221} yd [/tex]
Step-by-step explanation:
Use Pythagorean theorem to find x.
Thus, the sum of the square of the lengths of two legs of a right triangle equal the square of the hypotenuse, which is the longest side.
Thus,
[tex] x^2 = 11^2 + 10^2 [/tex]
[tex] x^2 = 121 + 100 [/tex]
[tex] x^2 = 221 [/tex]
[tex] x = \sqrt{221} yd [/tex]
Answer:
v/221 yd
Step-by-step explanation:
11y 10yd x ?
x=v/221 yd
yippie
What is 28% of 58?
Hhhhhhh
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]
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.
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
Find the sum of the first 10 terms of the following geometric sequences: 3,6,12,24,48
Answer:
3,069
Step-by-step explanation:
The sequence is doubling, so terms 1 through 10 are:
3, 6, 12, 24, 48, 96, 192, 384, 768, 1,536
3 + 6 + 12 + 24 + 48 + 96 + 192 + 384 + 768 + 1,536 = 3,069
) 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
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]
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
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, $f(x)=4x^2-3x+6$
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
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
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.
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.
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)
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 ^°^
22/25of a number is what percentage of that number?
Answer:
88%.
Step-by-step explanation:
Multiply the fraction by 100:
(22/25) * 100
= 22 * 4
= 88%.
How do you compress this?
[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]
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.
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.
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
Answer:
1/3
Step-by-step explanation:
there are twelve marbles total. there are 4 blue marbles.
4/12 = 1/3
What is the absolute value of the difference in the x-values between (1,7) and (3,11)
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
#SPJ2
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?
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
The length of time it takes college students to find a parking spot in the library parking lot follows a normal distribution with a mean of 6.5 minutes and a standard deviation of 1 minute. Find the probability that a randomly selected college student will find a parking spot in the library parking lot in less than 6.0 minutes.
Answer: P(X<6) = 0.3085 or 30.85%
Step-by-step explanation: Determine, first, z-score:
[tex]z = \frac{x-\mu}{\sigma}[/tex]
x is a random variable for time a student takes to find a spot, in this case, x=6:
[tex]z = \frac{6-6.5}{1}[/tex]
z = -0.5
Using z-score table, find z-score:
P(X<6) = P(z< -0.5)
P(X<6) = 0.3085
Probability of finding a parking spot in less than 6 minutes is approximately 30.85%.
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?
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]
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?
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
