Nina and Amy began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Nina took a test in English and earned a 71.8, and Amy took a test in Social Studies and earned a 60.7. Use the fact that all the students' test grades in the English class had a mean of 71.7 and a standard deviation of 11.7, and all the students' test grades in Social Studies had a mean of 60.6 and a standard deviation of 10.5 to answer the following questions.
a) Calculate the z-score for Nina's test grade.
b) Calculate the z-score for Amy's test grade.
c) Which person did relatively better?
i. Nina
ii. Amy
iii. They did equally well.

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

it might take 19 hours i might be wrong

Step-by-step explanation:

Answer:

continuous

rain does not fall in specific units like 1 inch , 2 inches etc... but 1.23456 etc..

Step-by-step explanation:

Answer:

r= 17.73174

Step-by-step explanation:

calculations

Answer:

30 gallons of each brand

Step-by-step explanation:

1 gallon of 60% + 1 gallon of 80% = 2 gallons 70% (60/2 = 30)

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.

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)

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

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]

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.

Given :-

To Find :-

Solution :-

We know that the circumference of the Circle with radius r is given by ,

=> C = 2πr .

=> C = 2 × 3.14 × 50 cm

=> C = 314 cm .

Hence the required answer is 314 cm .

Answer:

Step-by-step explanation:

b 75

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]

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:

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

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}

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

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.

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]

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%

Answer:

ur answer is correct

A =xy

A = 1.6×0.3 = 0.48

Step-by-step explanation:

D(.10) + Q(.25) = 4

I think

Answer:

D(.10) + Q(.25) = 4

Step-by-step explanation:

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.

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

Answer: 14 cm

Step-by-step explanation:

Rectangle:

x + x + (x - 2) + (x - 2) = 52

2x + 2(x - 2) = 52

2x + 2x - 4 = 52

4x = 52 + 4

4x = 56

x = 14

Answer:

8 are bad in math and 16 in physics

Step-by-step explanation:

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]

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

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.)

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

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