Sara is a librarian and works at least 10 hours per week. If Sara would like to work extra shifts, they are added to her
schedule in two-hour increments. Which equation models the number of hours that Sara will work at the library this
week? Assume x is the number of two-hour increments and y is the total number of hours worked.

Answer:

20 x 20 grid = 1066.67 cm wire

Step-by-step explanation:

Using unitary method

9 grid = 24 cm wire

1 grid = [tex]\frac{24}{9}[/tex] cm wire

Multiplying both sides by 400 (20 x 20)

400 grid = [tex]\frac{24}{9} * 400[/tex] cm

20 x 20 grid = 1066.67 cm wire

Answer:

a.) 8x + 6y

b.) 4x + 2y

Step-by-step explanation:

Simply add like terms together (x with x and y with y).

Answer:

The calculated  value Z = 3.775 > 1.96 at 0.05 level of significance

Null hypothesis is rejected

The Two Population proportion are not equal

Step-by-step explanation:

Given first sample size n₁ = 677

First sample proportion

                             [tex]p^{-} _{1} = \frac{x_{1} }{n_{1} } = \frac{172}{677} = 0.254[/tex]

Given second sample size n₂ = 3377

second sample proportion

                             [tex]p^{-} _{2} = \frac{x_{2} }{n_{2} } = \frac{654}{3377} = 0.1936[/tex]

Null Hypothesis : H₀ :  p₁ = p₂.

Alternative Hypothesis : H₁ :  p₁ ≠ p₂.

      Test statistic

                [tex]Z = \frac{p_{1} ^{-}-p^{-} _{2} }{\sqrt{P Q(\frac{1}{n_{1} } +\frac{1}{n_{2} }) } }[/tex]

where

        [tex]P = \frac{n_{1} p_{1} + n_{2} p_{2} }{n_{1}+n_{2} } = \frac{677 X 0.254+3377 X 0.1936}{677+3377}[/tex]

       P =  0.2036

      Q = 1 - P = 1 - 0.2036 = 0.7964

         [tex]Z = \frac{0.254- 0.1936 }{\sqrt{0.2036 X 0.7964(\frac{1}{677 } +\frac{1}{3377 }) } }[/tex]

        Z =  3.775

Critical value ∝=0.05

Z- value = 1.96

The calculated  value Z = 3.775 > 1.96 at 0.05 level of significance

Null hypothesis is rejected

The Two Population proportion are not equal

Answer:

a) Option D is correct.

H0​: μ = 71

Ha​: μ > 71

b) Option F is correct

z > 1.28

c) z = 2.85

d) Option C is correct.

Reject H0.There is sufficient evidence at the α = 0.10 level of significance to conclude that the true mean heart rate during laughter exceeds 71 beats per minute.

Step-by-step explanation:

a) For hypothesis testing, the first thing to define is the null and alternative hypothesis.

The null hypothesis plays the devil's advocate and usually takes the form of the opposite of the theory to be tested. It usually contains the signs =, ≤ and ≥ depending on the directions of the test.

While, the alternative hypothesis usually confirms the the theory being tested by the experimental setup. It usually contains the signs ≠, < and > depending on the directions of the test.

This question aims to test the the true mean heart rate during laughter exceeds 71 beats per minute.

Hence, the null hypothesis is that there isn't sufficient evidence to say that the true mean heart rate during laughter exceeds 71 beats per minute. That is, the true mean doesn't exceed 71 beats per minute.

And the alternative hypothesis is that there is sufficient evidence to say that the true mean heart rate during laughter exceeds 71 beats per minute.

Mathematically,

The null hypothesis is represented as

H₀: μ = 71

The alternative hypothesis is represented as

Hₐ: μ > 71

b) Using z-distribution, the rejection area is obtained from the confidence level at which the test is going to be performed. Since the hypothesis test tests only in one direction,

Significance level = (100% - confidence level)/2

0.10 = 10% = (100% - confidence level)/2

20% = 100% - (confidence level)

Confidence level = 100% - 20% = 80%

Critical value for 80% confidence level = 1.28

And since we are testing if the true mean heart rate during laughter exceeds 71 beats per minute, the rejection area would be

z > 1.28

c) The test statistic is given as

z = (x - μ)/σₓ

x = sample mean = 73.4

μ = 71

σₓ = standard error = (σ/√n)

σ = 8

n = Sample size = 90

σₓ = (8/√90) = 0.8433

z = (73.4 - 71) ÷ 0.8433

z = 2.846 = 2.85

d) Since the z-test statistic obtained, 2.85, is firmly in the rejection area, z > 1.28, we reject the null hypothesis, accept the alternative hypothesis and say that there is sufficient evidence at the α = 0.10 level of significance to conclude that the true mean heart rate during laughter exceeds 71 beats per minute.

Hope this Helps!!!

Answer:

39

Step-by-step explanation:

12+20+22+22+23=99

new mean=23

23*6=138

138-99=39

Answer:

180:300

Step-by-step explanation:

You first divide 480 by 8 because 3+5= 8 and then you multiply that answer (60) by 3 to get 180 and then you multiply it by 5 to get 300. So you get the ratio of 180:300.

Answer:

72√3

Step-by-step explanation:

30 60 90 triangles are what you start out with.

Step 1: 30-60-90

x = 12

WZ = 12√3

Step 2: Area formula

A = 1/2(12)(12√3)

*Since the 2 30-60-90 triangles are congruent, both segments of the base are 12

Plug it into the calc and you should get A = 72√3 as your final answer!

Answer:

25/88

Step-by-step explanation:

25 red marbles, 27 blue marbles, and 36 yellow marbles. = 88 marbles

P(red) = number of red/total

          = 25/88

Answer:

Dear user,

Answer to your query is provided below

Probability of choosing a red marble is 0.28 or (25/88)

Step-by-step explanation:

Total number of marbles = 88

Number of red marbles = 25

Probability = 25/88

Answer:

[tex]y = -\frac{7x}{3} - 24[/tex]

Step-by-step explanation:

We can model this function using the equation of a line:

[tex]y = ax + b[/tex]

Where a is the slope of the line and b is the y-intercept.

To find the values of a and b, we can use the two points given:

(-9, -3):

[tex]-3 = a * (-9) + b[/tex]

[tex]-9a + b = -3[/tex]

(-12, 4):

[tex]4 = a * (-12) + b[/tex]

[tex]-12a + b = 4[/tex]

If we subtract the second equation from the first one, we have:

[tex]-12a + b - (-9a + b) = 4 - (-3)[/tex]

[tex]-12a + 9a = 4 + 3[/tex]

[tex]-3a = 7[/tex]

[tex]a = -7/3[/tex]

Then, finding the value of b, we have:

[tex]-12a + b = 4[/tex]

[tex]28 + b = 4[/tex]

[tex]b = -24[/tex]

So the equation is:

[tex]y = -\frac{7x}{3} - 24[/tex]

Answer:

9x-11

Step-by-step explanation:

-5+2(x-3)+7x

Distribute

-5 +2x -6 +7x

-11 +9x

9x-11

Answer:

[tex]= 9x - 11 \\ [/tex]

Step-by-step explanation:

[tex] - 5 + 2(x - 3) + 7x \\ - 5 + 2x - 6 + 7x \\ - 5 - 6 + 2x + 7x \\ - 11 + 9x \\ = 9x - 11[/tex]

Answer:

Yes, the sample has a bias

Step-by-step explanation:

Bias is the term used in statistics to describe a systematic distortion in the samples obtained for the parameter being estimated. It is evident by obtaining values higher or lower than that of the average population for the parameter being measured. As such the data is a misrepresentation of the population and cannot be trusted to give a good indices of things.

This sample has a bias because the concerned citizen opted to use a convenience sampling instead of using random sampling. In random sampling, every individual has an equal chance of being chosen which is unlike the convenience sampling when only a specific group of individuals can be chosen. In this case, the bias was introduced when the citizen went to stand outside the courthouse with his petition, the citizen should have taken samples across diverse geographical locations and professional institutions. The implication of this sampling is that a significant percentage of the population has been sidelined (considering they would not be in or around the courthouse) from the sampling and the sampling has been restricted to only those who have business around the courthouse. The result is that whatever samples he/she obtains will not be an accurate representation of the parameter being measure from the population.

As such, the sampling technique is biased

Answer:

(a) S = {GH, GT, BH, BT, RH and RT}

(b) The value of P (A) is 0.15.

(c) A and B mutually exclusive.

(d) A and C are not mutually exclusive.

Step-by-step explanation:

There are 10 cards in a special deck of cards: 4 are green (G), 3 are blue (B), and 3 are red (R).

Also when a card is picked, its color of it is recorded. An experiment consists of first picking a card and then tossing a coin.

(a)

The sample space is:

S = {GH, GT, BH, BT, RH and RT}

(b)

A = a blue card is picked first, followed by landing a head on the coin toss

Compute the probability of event A as follows:

[tex]P(A)=P(B)\times P(H)[/tex]

         [tex]=\frac{3}{10}\times\frac{1}{2}\\\\=\frac{3}{20}\\\\=0.15[/tex]

Thus, the value of P (A) is 0.15.

(c)

B = a red or green is picked, followed by landing a head on the coin toss.

The result of the coin toss is same for both events A and B.

So, consider the events,

A as a blue card is picked first

B as a red or green is picked

There is no intersection point for the two events.

Thus, events A and B mutually exclusive.

(d)

C = a red or blue is picked, followed by landing a head on the coin toss.

The result of the coin toss is same for both events A and C.

So, consider the events,

A as a blue card is picked first

C as a red or blue is picked

There is an intersection point for the two events.

Thus, events A and C are not mutually exclusive.

Part(a): The sample space can be written as shown below:

[tex]S=\{GH,GT,BH,BT,RH,RT\}[/tex]

Part(b): The required probability is [tex]P(A)=0.15[/tex]

Part(c): The events A and B are mutually exclusive because of [tex]P( A\ AND\ B ) = 0[/tex] are equal to zero.

Part(d): The events A and C are not mutually exclusive because [tex]P( A\ AND\ C ) = 0[/tex] are not equal to zero.

A sample space is a collection of a set of possible outcomes of a random experiment. The sample space is represented using the symbol, “S”.

Part(a):

A special deck contains ten cards with colors red, green, and blue when the card is picked its color gets recorded, and after that coin will get tossed.

Then the sample space can be written as shown below:

[tex]S=\{GH,GT,BH,BT,RH,RT\}[/tex]

Part(b):

If A is the event that a blue card is picked first followed by landing ahead on the coin toss then the outcome it contains is 3 blue cards and 1 head.

Therefore the [tex]P(A)[/tex] is calculated below:

[tex]P(A):P(B)\timesP(H)\\=\frac{3}{10}\times\frac{1}{2}\\ =0.15[/tex]

Part(c):

Mutually exclusive events contain a probability [tex]P( A\ AND\ B ) = 0[/tex] that means there is no common outcome between them.

Here, it can be noticed that events A and B cannot happen at the same time. That means, the researcher cannot pick the same cards together. Either it could be red or green.

Hence, events A and B are mutually exclusive because of [tex]P( A\ AND\ B ) = 0[/tex] are equal to zero.

Part(d):

Mutually exclusive events contain a probability [tex]P( A\ AND\ C ) = 0[/tex]  which means there is no common outcome between them.

Here, it can be noticed that events A and C can happen at the same time because event C can contain all outcomes of event A.

Hence, events A and C are not mutually exclusive because [tex]P( A\ AND\ C ) = 0[/tex] are not equal to zero.

Learn more about the topic samples space:

https://brainly.com/question/10684603

Answer:

2 total roots

x = -1/3, 3/4

Step-by-step explanation:

We can use the discriminant b² - 4ac to find how many roots a polynomial has.

Answer:

Step-by-step explanation:

Edginuity 2021

Answer:

He served as Assistant Secretary of the Navy under President William McKinley

hope i helped

-lvr

Answer:

You can add graph by using the edit button and uploading a picture of the screen. if you then cut the picture before uploading so it just shows the graphand not the question. We cna then try answer for you.

Step-by-step explanation:

Generally graphs starting at point x=0 would show a different value for y by looking and counting up to its temperature.

if this shows positive it would be above the x axis line if it shows negative it would be a minus value below the x axis line under zero on y.

Therefore when we get to hr 2 and see this change you can count across and count up and see the rate of change is either 1,2,3,4,56,7,8 etc difference or 1x 2x 3x 4 x 5x 6 x as multiples.This then indicates a scale change at certain points.

Answer:

The future value of the annuity due to the nearest cent is $2956.

Step-by-step explanation:

Consider the provided information:

It is provided that monthly payment is $175, interest is 7% and time is 11 years.

The formula for the future value of the annuity due is:

Now, substitute P = 175, r = 0.07 and t = 11 in above formula.

Hence, the future value of the annuity due to the nearest cent is $2956.

Step-by-step explanation:

Answer:

the correct answer is

Step-by-step explanation:

So, the probability is:P(greater than 4)=26=13. This is a theoretical probability, which is the observed number of favorable outcomes out of a certain number of trials. For instance, suppose you rolled the six-sided die five times, and got the following results:2,6,4,5,6

hope this help you!!!!!

Answer:

1/5 chance.

Step-by-step explanation:

There is only one number, 5, that is greater than 4 and there are 5 total numbers so there is a 1/5 chance selecting that number.

Answer:

(a) The probability that at least one individual with a reservation cannot be accommodated on the trip is 0.4202.

(b) The expected number of available places when the limousine departs is 0.338.

Step-by-step explanation:

Let the random variable Y represent the number of passenger reserving the trip shows up.

The probability of the random variable Y is, p = 0.70.

The success in this case an be defined as the number of passengers who show up for the trip.

The random variable Y follows a Binomial distribution with probability of success as 0.70.

(a)

It is provided that n = 6 reservations are made.

Compute the probability that at least one individual with a reservation cannot be accommodated on the trip as follows:

P (At least one individual cannot be accommodated) = P (X = 5) + P (X = 6)

[tex]={6 \choose 5}\ (0.70)^{5}\ (1-0.70)^{6-5}+{6 \choose 6}\ (0.70)^{6}\ (1-0.70)^{6-6}\\\\=0.302526+0.117649\\\\=0.420175\\\\\approx 0.4202[/tex]

Thus, the probability that at least one individual with a reservation cannot be accommodated on the trip is 0.4202.

(b)

The formula to compute the expected value is:

[tex]E(Y) = \sum X\cdot P(X)[/tex]

[tex]P (X=0)={6 \choose 0}\ (0.70)^{0}\ (1-0.70)^{6-0}=0.000729\\\\P (X=1)={6 \choose 1}\ (0.70)^{1}\ (1-0.70)^{6-1}=0.010206\\\\P (X=2)={6 \choose 2}\ (0.70)^{2}\ (1-0.70)^{6-2}=0.059535\\\\P (X=3)={6 \choose 3}\ (0.70)^{3}\ (1-0.70)^{6-3}=0.18522\\\\P (X=4)={6 \choose 4}\ (0.70)^{4}\ (1-0.70)^{6-4}=0.324135[/tex]

Compute the expected number of available places when the limousine departs as follows:

[tex]E(Y) = \sum X\cdot P(X)[/tex]

         [tex]=(4\cdot 0.000729)+(3\cdot 0.010206)+(2\cdot 0.059535)+(1\cdot 0.18522)\\+(0\cdot 0.324135)\\\\=0.002916+0.030618+0.11907+0.18522+0\\\\=0.337824\\\\\approx 0.338[/tex]

Thus, the expected number of available places when the limousine departs is 0.338.

Answer:

44.43% probability that among 40 adults (ages 70 and older) chosen at random more than 22 percent will have been told by their doctor that they have cancer

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal probability distribution

When the distribution is normal, we use the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem estabilishes 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]

In this question, we have that:

[tex]p = 0.211, n = 40[/tex]

So

[tex]\mu = 0.211, s = \sqrt{\frac{0.211*0.789}{40}} = 0.0645[/tex]

What is the probability that among 40 adults (ages 70 and older) chosen at random more than 22 percent will have been told by their doctor that they have cancer

This is 1 subtracted by the pvalue of Z when X = 22. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

By the Central Limit Theorem

[tex]Z = \frac{X - \mu}{s}[/tex]

[tex]Z = \frac{0.22 - 0.211}{0.0645}[/tex]

[tex]Z = 0.14[/tex]

[tex]Z = 0.14[/tex] has a pvalue of 0.5557

1 - 0.5557 = 0.4443

44.43% probability that among 40 adults (ages 70 and older) chosen at random more than 22 percent will have been told by their doctor that they have cancer

Answer:

Step-by-step explanation:

Hi,

the function is defined for all reals so the domain is [tex]]-\infty;+\infty[[/tex]

for x real

|x| >= 0

so f(x) >= 4

so the range is [tex][4;+\infty[[/tex]

do not hesitate if you need any further explanation

hope this helps

Answer:

Domain: (-∞,∞) Range: (4,∞)

Step-by-step explanation:

I will do 12 and 14 as examples.

12) Angles of a triangle add up to 180°.

m∠P + m∠Q + m∠R = 180

5x − 14 + x − 5 + 2x − 9 = 180

8x − 28 = 180

8x = 208

x = 26

m∠P = 5x − 14 = 116

m∠Q = x − 5 = 21

m∠R = 2x − 9 = 43

14) If two sides of a triangle are equal, then the angles opposite those sides are also equal.

(Conversely, if two angles are equal, then the sides opposite those angles are also equal.  Such a triangle is called an isosceles triangle.)

BC ≅ BD, so m∠C = m∠D.

5x − 19 = 2x + 14

3x = 33

x = 11

m∠B = 13x − 35 = 108

m∠C = 5x − 19 = 36

m∠D = 2x + 14 = 36

Answer: Undefined

Step-by-step explanation:

For this problem, we know that 3ˣ=-9. All we have to do is figure out what x is.

We know that any integer raised to the power cannot be negative. The closest answer we can get is x=2 because 3²=9. Unfortunately, we are looking for -9. Therefore, this x is undefined.

Answer:

9

Step-by-step explanation:

f(x) = (x + 1)^2

Let x=2

f(2) = (2 + 1)^2

     = 3^2

     = 9

Answer:

Step-by-step explanation:

The question is incomplete. The complete question is

The manager of the Danvers-Hilton Resort Hotel stated that the mean guest bill for a weekend is $600 or less. A member of the hotel’s accounting staff noticed that the total charges for guest bills have been increasing in recent months. The accountant will use a sample of

weekend guest bills to test the manager’s claim.

a. Which form of the hypotheses should be used to test the manager’s claim? Explain.

1) H0:μ ≥ 600

Ha:μ < 600

2) H0:μ ≤ 600

Ha:μ > 600

3) H0:μ=600

Ha:μ≠600

b. What conclusion is appropriate when H0 cannot be rejected?

c. What conclusion is appropriate when H0 can be rejected?

Solution:

a) the hypotheses should be used to test the manager’s claim is

H0:μ ≤ 600

Ha:μ > 600

This is because the already known or assumed mean guest bill for a weekend is 600 or less. This forms the null hypothesis. The alternative is the opposite of the null hypothesis. Since the alternative states that it is increasing, the sign,> would be used.

b) If H0 cannot be rejected, it means that there is no sufficient evidence to reject H0 at the given level of significance.

c) if H0 can be rejected, it means that there is sufficient evidence to reject H0 at the given level of significance.

Answer:

a) Null hypothesis: the drug is equally effective for men and women (company's claim)

Alternative hypothesis: the drug effectiveness significantly differs for men and women.

[tex]H_0: \pi_1-\pi_2=0\\\\H_a:\pi_1-\pi_2\neq 0[/tex]

b) If the P-value is smaller than the significance level, the null hypothesis is rejected. If not, the null hypothesis failed to be rejected.

c) In the explanation.

d) As the P-value (0.0342) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

There is enough evidence to support the claim that the drug effectiveness significantly differs for men and women.

The company's claim is rejected.

Step-by-step explanation:

This is a hypothesis test for the difference between proportions.

The claim of the company, will be stated in the null hypothesis. We will test if there is evidence against that claim to reject it or not.

Then, the test claim is that the drug effectiveness significantly differs for men and women.

The null and alternative hypothesis are:

[tex]H_0: \pi_1-\pi_2=0\\\\H_a:\pi_1-\pi_2\neq 0[/tex]

The significance level is 0.05.

The sample 1 (women), of size n1=100 has a proportion of p1=0.38.

The sample 2 (men), of size n2=200 has a proportion of p2=0.51.

The difference between proportions is (p1-p2)=-0.13.

[tex]p_d=p_1-p_2=0.38-0.51=-0.13[/tex]

The pooled proportion, needed to calculate the standard error, is:

[tex]p=\dfrac{X_1+X_2}{n_1+n_2}=\dfrac{38+102}{100+200}=\dfrac{140}{300}=0.467[/tex]

The estimated standard error of the difference between means is computed using the formula:

[tex]s_{p1-p2}=\sqrt{\dfrac{p(1-p)}{n_1}+\dfrac{p(1-p)}{n_2}}=\sqrt{\dfrac{0.467*0.533}{100}+\dfrac{0.467*0.533}{200}}\\\\\\s_{p1-p2}=\sqrt{0.002489+0.001244}=\sqrt{0.003733}=0.061[/tex]

Then, we can calculate the z-statistic as:

[tex]z=\dfrac{p_d-(\pi_1-\pi_2)}{s_{p1-p2}}=\dfrac{-0.13-0}{0.061}=\dfrac{-0.13}{0.061}=-2.1276[/tex]

This test is a two-tailed test, so the P-value for this test is calculated as (using a z-table):

[tex]P-value=2\cdot P(z<-2.1276)=0.0342[/tex]

As the P-value (0.0342) is smaller than the significance level (0.05), the effect is significant.

The null hypothesis is rejected.

There is enough evidence to support the claim that the drug effectiveness significantly differs for men and women.

Answer:

1/26

Step-by-step explanation:

There is 1 four of spades, and 1 ace of clubs.

So the probability is 2/52, or 1/26.

Answer:

P(four of spades or ace of clubs)= 1/26

Step-by-step explanation:

In a deck of 52 cards, there is one four of spaces and one ace of clubs. we want to find the probability of selecting those cards.

P(four of spades or ace of clubs)=four of spades+ace of clubs/total cards

There is 1 four of spades and 1 ace of clubs. 1+1=2

P(four of spades or ace of clubs)=2/total cards

There are 52 total cards in a deck.

P(four of spades or ace of clubs)=2/52

This fraction can be simplified. Both the numerator (top number) and denominator (bottom number) can be divided by 2.

P(four of spades or ace of clubs)= (2/2) / (52/2)

P(four of spades or ace of clubs)= 1/26

Answer:

The sample correlation coefficient is, r = 0.8722.

The equation of the least-squares line is:

[tex]y= -0.161+0.154x[/tex]

Step-by-step explanation:

(a)

The scatter diagram displaying the data for X : total number of jobs in a given neighborhood and Y : number of entry-level jobs in the same neighborhood is shown below.

(b)

The table attached below verifies the values of [tex]\sum X,\ \sum Y,\ \sum X^{2},\ \sum Y^{2}\ \text{and}\ \sum XY[/tex].

The sample correlation coefficient is:

[tex]\begin{aligned}r~&=~\frac{n\cdot\sum{XY} - \sum{X}\cdot\sum{Y}} {\sqrt{\left[n \sum{X^2}-\left(\sum{X}\right)^2\right] \cdot \left[n \sum{Y^2}-\left(\sum{Y}\right)^2\right]}} \\r~&=~\frac{ 6 \cdot 1163 - 201 \cdot 30 } {\sqrt{\left[ 6 \cdot 7759 - 201^2 \right] \cdot \left[ 6 \cdot 182 - 30^2 \right] }} \approx 0.8722\end{aligned}[/tex]

Thus, the sample correlation coefficient is, r = 0.8722.

(c)

The slope and intercept are:

[tex]\begin{aligned} a &= \frac{\sum{Y} \cdot \sum{X^2} - \sum{X} \cdot \sum{XY} }{n \cdot \sum{X^2} - \left(\sum{X}\right)^2} = \frac{ 30 \cdot 7759 - 201 \cdot 1163}{ 6 \cdot 7759 - 201^2} \approx -0.161 \\ \\b &= \frac{ n \cdot \sum{XY} - \sum{X} \cdot \sum{Y}}{n \cdot \sum{X^2} - \left(\sum{X}\right)^2} = \frac{ 6 \cdot 1163 - 201 \cdot 30 }{ 6 \cdot 7759 - \left( 201 \right)^2} \approx 0.154\end{aligned}[/tex]

The equation of the least-squares line is:

[tex]y= -0.161+0.154x[/tex]

(d)

The least-squares line is graphed in the diagram below.

Answer: The distance of the shortest route of return is 400

Step-by-step explanation:

The direction of travel of the plane forms a right angle triangle ABC as shown in the attached photo. C represents the starting point of the plane. To determine the distance of the shortest by which the plane can return to its starting point, BC, we would apply the Pythagorean theorem which is expressed as

Hypotenuse² = opposite side² + adjacent side²

BC² = 320² + 240²

BC² = 160000

BC = √160000

BC = 400

Answer:

Step-by-step explanation: