Answer:
a) [tex]Z = 0.0085[/tex]
b) [tex]Z = 0.0095[/tex]
c) ii. Amy
Step-by-step explanation:
Z-score:
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Question a:
Nina took a test in English and earned a 71.8. In the English class had a mean of 71.7 and a standard deviation of 11.7.
This means that [tex]X = 71.8, \mu = 71.7, \sigma = 11.7[/tex]
So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{71.8 - 71.7}{11.7}[/tex]
[tex]Z = 0.0085[/tex]
Question b:
Amy took a test in Social Studies and earned a 60.7. Students' test grades in Social Studies had a mean of 60.6 and a standard deviation of 10.5.
This means that [tex]X = 60.7, \mu = 60.6, \sigma = 10.5[/tex]
So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{60.7 - 60.6}{10.5}[/tex]
[tex]Z = 0.0095[/tex]
c) Which person did relatively better?
Amy had a higher z-score, so she did relatively better.
HELP PLEASE!!! So for this problem is got 0.48 however I just wanted to confirm that my answer is correct. Can someone please help me if the answer is wrong and how to solve it. Thank your for your time
Answer:
ur answer is correct
A =xy
A = 1.6×0.3 = 0.48
How can one estimate a car annual fuel expense
Answer:
determine the number of miles the car drives in a year.
divide that number by the cars average MPG (miles per gallon) then multiply that number by the average cost of a gallon of gas in your area.
Step-by-step explanation:
Using law of sines please show process!!!
Let the <C=x
We know in a triangle
☆Sum of angles=180°
[tex]\\ \sf\longmapsto 51+26+x=180[/tex]
[tex]\\ \sf\longmapsto 77+x=180[/tex]
[tex]\\ \sf\longmapsto x=180-77[/tex]
[tex]\\ \sf\longmapsto x=103°[/tex]
Melanie has D dimes and Q quarters. She has no less than $4 worth of coins altogether. Write this situation as an inequality.
Step-by-step explanation:
D(.10) + Q(.25) = 4
I think
Answer:
D(.10) + Q(.25) = 4
Step-by-step explanation:
What is the value of k?
K=?
9514 1404 393
Answer:
k = 2
Step-by-step explanation:
The geometric mean theorem for the altitude tells you ...
ON = √(OL·OM)
ON² = OL·OM . . . . . square both sides
4² = 8·k . . . . . . . . substitute values
k = 16/8 = 2 . . . . divide by the coefficient of k
_____
Additional comment
The geometric mean theorem for the legs tells you ...
MN = √(MO·ML) ⇒ l = 2√5
LN = √(LO·LM) ⇒ m = 4√5
These relations come from the fact that corresponding sides of the right triangles are proportional. (All of the triangles are similar.)
A telephone exchange operator assumes that 9% of the phone calls are wrong numbers. If the operator is correct, what is the probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%
Answer:
0.0264 = 2.64% probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
A telephone exchange operator assumes that 9% of the phone calls are wrong numbers.
This means that [tex]p = 0.09[/tex]
Sample of 448
This means that [tex]n = 448[/tex]
Mean and standard deviation:
[tex]\mu = p = 0.09[/tex]
[tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.09*0.91}{448}} = 0.0135[/tex]
What is the probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%?
More than 9% + 3% = 12 or less than 9% - 3% = 6%. Since the normal distribution is symmetric, these probabilities are the same, so we find one of them and multiply by 2.
Probability it is less than 6%
P-value of Z when X = 0.06. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{0.06 - 0.09}{0.0135}[/tex]
[tex]Z = -2.22[/tex]
[tex]Z = -2.22[/tex] has a p-value of 0.0132
2*0.0132 = 0.0264
0.0264 = 2.64% probability that the proportion of wrong numbers in a sample of 448 phone calls would differ from the population proportion by more than 3%
If A = {x, y, z} then the number of non-empty subsets of A is ________.
a) 8 b) 5 c) 6 d) 7
Answer:
(d) 7
Step-by-step explanation:
The total number of subsets that can be derived from a set with n elements is given by;
2ⁿ
Out of these subsets, there is one empty set. Therefore, the total number of non-empty subsets is given by;
2ⁿ - 1
Given:
A = {x, y, z}
Set A has 3 elements. This means that n = 3
Therefore, the total number of subsets that can be derived from set A is
2ⁿ = 2³ = 8
One of these 8 subsets is an empty set, therefore, the total number of non-empty subsets of A is;
2ⁿ - 1 = 2³ - 1
8 - 1 = 7
This can be checked by writing all the possible subsets of A as follows;
∅
{x}
{y}
{z}
{x, y}
{y, z}
{x, z}
{x, y, z}
Removing the empty set ∅, the non-empty subsets of A are;
{x}
{y}
{z}
{x, y}
{y, z}
{x, z}
{x, y, z}
Which expression gives the best estimate of 30 percent of 61?
The answers are below:
Hurry, please!
Answer:
it would be 1/4(60)
Step-by-step explanation:
30 percent of 61 is 18.3 and 1/4 of 60 is 15 which is closest to 18.3
70. If set A consists of (3, 5, 7, 9) and set B consists of (1, 2, 3, 5, 8, 13), what is the average of the union of set A and set B?
A) 6
B) 3
C) 48
D) 56
⚠️will give brainliest to the best answer
Step-by-step explanation:
the answer would be 6. brrr
A) 6
{1,2,3,5,7,8,9,13}
The average is going to be 6.
سا (a) From the definition of derivatives determine dy÷dx if y = -2÷x
Step-by-step explanation:
Given: [tex]y = -\dfrac{2}{x}[/tex]
Derivative of a power function [tex]x^n[/tex]:
[tex]\dfrac{d}{dx}(x^n) = nx^{n-1}[/tex]
Therefore,
[tex]\dfrac{dy}{dx}=-2(-1)x^{-2} = \dfrac{2}{x^2}[/tex]
A single, six-sided die is rolled. Find the probability of rolling an even number or a number less than 6 .
Answer:
P=1
Step-by-step explanation:
P(even or less than 6) = P(even)+P(less than 6) -P(even ∩ less than 6)
P(even)=3/6 (numbers 2,4, and 6)
P(less than 6) =5/6 (numbers 1,2,3,4, and 5)
P(even ∩ less than 6)=2/6 (numbers 2 and 4)
(3/6)+(5/6) -(2/6) = (3+5-2)/6 = 6/6=1
In a pen of goats and chickens, there are 40 heads. and 130 feet How many goats and chickens are there?
Answer:
25 goat and 15 chicken
Step-by-step explanation:
Say the number of goats is G, then the number of chickens is 40 - G as there are 40 heads and each chicken and each goat has one head.
The number of feet is 130
So 2(40 - G) + 4G = 130
So 80 - 2G + 4G = 130
2G = 50
G = 25
25 goats and 15 chickens
Is the random variable described discrete or continuous? The amount of rain during the next thunderstorm.
Answer:
continuous
rain does not fall in specific units like 1 inch , 2 inches etc... but 1.23456 etc..
Step-by-step explanation:
A chemical company makes two brands of antifreeze the first brand contains 65% pure antifreeze and the second brand contains 80% pure antifreeze in order to obtain 60 gallons of a mixture that contains 70% pure antifreeze how many gallons of each brand of antifreeze must be used
Answer:
30 gallons of each brand
Step-by-step explanation:
1 gallon of 60% + 1 gallon of 80% = 2 gallons 70% (60/2 = 30)
A recipe for chocolate chip cookies calls for 3 1/3 cups of flour. If you are making 2 1/4 recipes, how many cups of flour are needed.
Answer:
THIS IS THE ANSWER
Step-by-step explanation:
1 1/2 = 3/2
2 1/3 = 7/3
3/2 * 7/3 = 21/6 = 3 3/5 = 3 1/2 cups
PLEASE MARK ME AS A BRAINLIST!Need help on this problem
Answer:
Step-by-step explanation:
[tex]2(x-2)^2=8(7+y)\\2(x-2)^2=56+8y \Rightarrow y={1\over{8}}[2(x-2)^2-56]={1\over{4}}(x-2)^2-7\\finally\\y={1\over{4}}(x-2)^2-7\\let ~change~x~and~y\\x={1\over{4}}(y-2)^2-7\\x+7={1\over{4}}(y-2)^2\\4(x+7)=(y-2)^2\\y-2=\pm\sqrt{4(x+7)}\\\\y=2\pm\sqrt{4x+28}[/tex]
solve the following by factolisation formula
1. x(2x+1)=0
2.4xsquere-11-3x=0
1.
X = 0
2x + 1 = 0
X = 0
X = - ½ (Because we brought the numbers from one side to the other)
2.
Not sure for number 2.
in a class of 38 student,30 are good in mathematics and 22 are good in physics how many students are good in both mathematics and physics
Answer:
8 are bad in math and 16 in physics
Step-by-step explanation:
The proportion of brown M&M's in a milk chocolate packet is approximately 14% (Madison, 2013). Suppose a package of M&M's typically contains 52 M&M's
Answer:
7 brown M&Ms.
Step-by-step explanation:
This question is not complete, but I will assume that the final question is how many brown M&Ms will be in this package.
0.14 × 52 is our equation.
The answer is 7.28. We cannot have .28 of a brown M&M in a package (unless you count the broken ones) so there will be, on average, 7 brown M&Ms in a package.
(again, the question is incomplete, so this may not be the answer)
Find sin d, sin e, cos d, and cos e. Write each answer as a fraction in simplest form
Answer:
r= 17.73174
Step-by-step explanation:
calculations
\int (x+1)\sqrt(2x-1)dx
Answer:
[tex]\int (x+ 1) \sqrt{2x-1} dx = \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{15}(2x-1)^{\frac{5}{2}} + C[/tex]
Step-by-step explanation:
[tex]\int (x+1)\sqrt {(2x-1)} dx\\Integrate \ using \ integration \ by\ parts \\\\u = x + 1, v'= \sqrt{2x - 1}\\\\v'= \sqrt{2x - 1}\\\\integrate \ both \ sides \\\\\int v'= \int \sqrt{2x- 1}dx\\\\v = \int ( 2x - 1)^{\frac{1}{2} } \ dx\\\\v = \frac{(2x - 1)^{\frac{1}{2} + 1}}{\frac{1}{2} + 1}} \times \frac{1}{2}\\\\v= \frac{(2x - 1)^{\frac{3}{2}}}{\frac{3}{2}} \times \frac{1}{2}\\\\v = \frac{2 \times (2x - 1)^{\frac{3}{2}}}{3} \times \frac{1}{2}\\\\v = \frac{(2x - 1)^{\frac{3}{2}}}{3}[/tex]
[tex]\int (x+1)\sqrt(2x-1)dx\\\\ = uv - \int v du[/tex]
[tex]= (x +1 ) \cdot \frac{(2x - 1)^{\frac{3}{2}}}{3} - \int \frac{(2x - 1)^{\frac{3}{2}}}{3} dx \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ [ \ u = x + 1 => du = dx \ ][/tex]
[tex]= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \int (2x - 1)^{\frac{3}{2}}} dx\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \times ( \frac{(2x-1)^{\frac{3}{2} + 1}}{\frac{3}{2} + 1}) \times \frac{1}{2}\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{3} \times ( \frac{(2x-1)^{\frac{5}{2}}}{\frac{5}{2} }) \times \frac{1}{2}\\\\= \frac{1}{3}(x+1) (2x - 1)^{\frac{3}{2} } - \ \frac{1}{15} \times (2x-1)^{\frac{5}{2}} + C\\\\[/tex]
The width of a rectangle is 2 cm less than its length. The perimeter is 52 cm. The length is:
14 cm.
12 cm.
9 cm.
None of these choices are correct.
Answer: 14 cm
Step-by-step explanation:
Rectangle:
Length = xWidth = x - 2x + x + (x - 2) + (x - 2) = 52
2x + 2(x - 2) = 52
2x + 2x - 4 = 52
4x = 52 + 4
4x = 56
x = 14
Find the circumference of a circle with a diameter of 50 centimeters. Round your answer to the nearest
centimeter.
Given :-
Diameter of circle = 50 cm .To Find :-
The circumference of the Circle.Solution :-
We know that the circumference of the Circle with radius r is given by ,
=> C = 2πr .
Here r is 50cm .=> C = 2 × 3.14 × 50 cm
=> C = 314 cm .
Hence the required answer is 314 cm .
Answer:
Step-by-step explanation:
b 75
PLEASE HELP SOON Find the value of x. Round to the nearest tenth. 27° х 34° 11 X = ? [?] 9 Law of Sines: sin A sin C sin B b a Enter
The picture of the problem has been attached below :
Answer:
13.5
Step-by-step explanation:
Applying the sine rule to solve for x
SinA /a = SinB / b = SinC/ c
Sin 34 / x = Sin 27/11
Cross multiply :
11 * sin34 = x * sin 27
6.1511219 = 0.4539904x
Divide both sides by 0.4539904
6.1511219/0.4539904 = x
13.549 = x
x = 13.5
The mean incubation time of fertilized eggs is 19 days. Suppose the incubation times are approximately normally distributed with a standard deviation of 1 day. Answer the following. For each question draw an appropriate distribution function (graph) to represent the data, shade the desired area, and show all work, including what you input into your calculator to attain your results.
(A) The 14th percentile for incubation times is __ days.
(B) The incubation times that make up the middle 97% of fertilized eggs are __ to __ days.
Answer:
a)17.92
b) 16.83 .... 21.17
Step-by-step explanation:
ρ→ z
0.14 = -1.080319341
-1.080 = (x - 19)/1 = 17.92
~~~~~~~~~~~~~~~~~~
3% / 2 = 1.5%
1.5% - 98.5%
ρ→ z
0.015 = -2.170090378 .... -2.17 = (x-19) =16.83
0.985 = 2.170090378 .... 2.17 = (x-19) =21.17
Question 8
Points 3
Identify the functions whose lines are parallel.
0 3x + 2y = 45 and 8x + 4y = 135
x + y = 25 and 2x + y = 15
O 2x + 2y = 50 and 4x + 2y = 90
O 2x + 2y = 4 and 4x + 4y = 16
Answer:
2x + 2y = 4 and 4x + 4y = 16
Step-by-step explanation:
For two lines to be parallel, they must have the same slope.
To determine the correct answer to the question, we shall determine the slope of each equation in the given options to see which have the same slope. This can be obtained as follow:
1st option:
3x + 2y = 45 and 8x + 4y = 135
We shall rearrange the above equations to look like y = mx + c
NOTE: m is the slope.
3x + 2y = 45
rearrange
2y = –3x + 45
Divide both side by 2
y = –3x/2 + 45/2
Slope (m) = –3/2
8x + 4y = 135
Rearrange
4y = –8x + 135
Divide both side by 4
y = –8x/4 + 135/4
Slope (m) = –8/4 = –2
The two equation has different slopes. Thus, they are not parallel.
2nd option:
x + y = 25 and 2x + y = 15
x + y = 25
Rearrange
y = –x + 25
Slope (m) = –1
2x + y = 15
Rearrange
y = –2x + 15
Slope (m) = –2
The two equations has different slopes. Thus, they are not parallel.
3rd option:
2x + 2y = 50 and 4x + 2y = 90
2x + 2y = 50
Rearrange
2y = –2x + 50
Divide both side by 2
y = –2x/2 + 50/2
Slope (m) = –2/2 = –1
4x + 2y = 90
Rearrange
2y = –4x + 90
Divide both side by 2
y = –4x/2 + 90/2
Slope (m) = –4/2 = –2
The two equations has different slopes. Thus, they are not parallel.
4th option:
2x + 2y = 4 and 4x + 4y = 16
2x + 2y = 4
Rearrange
2y = –2x + 4
Divide both side by 2
y = –2x/2 + 4/2
Slope (m) = –2/2 = –1
4x + 4y = 16
Rearrange
4y = –4x + 16
Divide both side by 4
y = –4x/4 + 16/4
Slope (m) = –4/4 = –1
The two equations have the same slopes. Thus, they are parallel.
75. In the figure below, what is the slope of
the diagonal AC of the rectangle ABCD?
9514 1404 393
Answer:
A. 3/2
Step-by-step explanation:
Point C is 3 units higher and 2 units right of point A. The slope is ...
slope = rise/run = 3/2
aulo uses an instrument called a densitometer to check that he has the correct ink colour.
For this print job the acceptable range for the reading on the densitometer is 1.8 ± 10%.
What is the acceptable range for the densitometer reading?
Answer:
The range is from 1.62 to 1.98.
Step-by-step explanation:
We have to solve for the percentage of the particular value if the range of the answer should be +/- 10% of the particular value.
The value given is 1.8, we thus want to find 10% of that: 1.8 * 10/100 = 0.18
Then, add this value to the original value of 1.8: 1.8+0.18 = 1.98
Furthermore, subtract .18 from from the original value of 1.8: 1.8-0.18 = 1.62
The range will be between these two numbers, so the range is from 1.62 to 1.98.
a girl painted a rectangular-shaped portrait which is 10 inches long and 8 inches wide. if she trimmed 2/1/2 inches on both sides of the width and 2 inches on one side of the length, what would be the resulting area?
Answer:
32 in^2
Step-by-step explanation:
8-2=6, 6-2=4. 4 inches wide
10-2=8. 8 Inches tall.
4*8=32
Working to
(simplify y
Lisa, an experienced shipping clerk, can fill a certain order in 7 hours, Bill, a new clerk, needs 9 hours to do the
same job. Working together, how long will it take them to fill the order?
it might take 19 hours i might be wrong
Step-by-step explanation:
