Solution Found!

Solved: Driving Age According to a Gallup poll, 60% of

Chapter 11, Problem 7RE

(choose chapter or problem)

Get Unlimited Answers
QUESTION:

Driving Age According to a Gallup poll, 60% of U.S. women 18 years old or older stated that the minimum driving age should be 18. In a random sample of 15 U.S. women 18 years old or older, find the probability that:

(a) Exactly 10 believe that the minimum driving age should be 18.

(b) Fewer than 5 believe that the minimum driving age should be 18.

(c) At least 5 believe that the minimum driving age should be 18.

(d) Between 7 and 12, inclusive, believe that the minimum driving age should be 18.

(e) In a random sample of 200 U.S. women 18 years old or older, what is the expected number who believe that the minimum driving age should be 18? What is the standard deviation?

(f) If a random sample of 200 U.S. women 18 years old or older resulted in 110 who believe that the minimum driving age should be 18, would this be unusual? Why?

Questions & Answers


(1 Reviews)

QUESTION:

Driving Age According to a Gallup poll, 60% of U.S. women 18 years old or older stated that the minimum driving age should be 18. In a random sample of 15 U.S. women 18 years old or older, find the probability that:

(a) Exactly 10 believe that the minimum driving age should be 18.

(b) Fewer than 5 believe that the minimum driving age should be 18.

(c) At least 5 believe that the minimum driving age should be 18.

(d) Between 7 and 12, inclusive, believe that the minimum driving age should be 18.

(e) In a random sample of 200 U.S. women 18 years old or older, what is the expected number who believe that the minimum driving age should be 18? What is the standard deviation?

(f) If a random sample of 200 U.S. women 18 years old or older resulted in 110 who believe that the minimum driving age should be 18, would this be unusual? Why?

ANSWER:

Step 1 of 2 :  

 According to a Gallup poll, 60% of U.S. women 18 years old or older stated that the minimum driving age should be 18. In a random sample of 15 U.S. women 18 years old or older, find the probability that.

\(X \sim\) binomial distribution with parameters n and p.

Where , n=15 and p=60%=0.6.

a) Exactly 10 believe that the minimum driving age should be 18.

\(\begin{array}{l} \mathrm{P}(\mathrm{x})={ }^{n_{c}}{ }_{x} p^{x} q^{n-x} ; \text { where, } \mathrm{q}=1-\mathrm{p} . \\ \begin{aligned} \mathrm{P}(\mathrm{x}=10)=15 c_{10}(0.6)^{10 *}(1-0.6)^{15-10}=3003^{*} 0.006{ }^{*} 0.01024 \\ \mathrm{P}(\mathrm{X}=10)=0.1859 . \end{aligned} \end{array}\)

b) Fewer than 5 believe that the minimum driving age should be 18.

\(\begin{array}{l} \mathrm{P}(\mathrm{X}<5)=\mathrm{P}(\mathrm{x}=1)+\mathrm{P}(\mathrm{x}=2)+\mathrm{P}(\mathrm{x}=3)+\mathrm{P}(\mathrm{x}=4) \\ =15 c_{1} \\ (0.6)^{1 *}(1-0.6)^{15-1}+15 c_{2}(0.6)^{2} *(1-0.6)^{15-2}+15 c_{3}(0.6)^{3} *(1-0.6)^{15-3}+15 c_{4}(0.6)^{4} *(1-0.6)^{15-4} \\ =0.000024+0.00025+0.0016+0.0074 \\ =0.0093 \\ \mathrm{P}(\mathrm{X}<5)=0.0093 \end{array}\)

Add to cart

Reviews

Review this written solution for 172920) viewed: 2142 isbn: 9780321838704 | Fundamentals Of Statistics - 4 Edition - Chapter 6.2 - Problem 7re

Thank you for your recent purchase on StudySoup. We invite you to provide a review below, and help us create a better product.

Textbook: Fundamentals of Statistics

Click to rate

Write a review below (optional):

Submit Review
×

Thanks for your review!

Think of all the students you've helped. Nice job!


Study Tools You Might Need

Not The Solution You Need? Search for Your Answer Here:

×

Login

Login or Sign up for access to all of our study tools and educational content!

Forgot password?
Register Now

×

Register

Sign up for access to all content on our site!

Or login if you already have an account

×

Reset password

If you have an active account we’ll send you an e-mail for password recovery

Or login if you have your password back