Question

When 500 college students were surveyed, 30% said that they own their car. Construct a 95% confidence interval for the proportion of college students who say they own their cars. DON'T JUST GIVE THE ANSWER - SHOW WORK AND EXPLAIN YOUR PROCESS EACH STEP OF THE WAY SO THAT I CAN FOLLOW WHAT YOU DID AND CHECK YOUR WORK.

Answer 1

Given:

Samples size, n = 500

Sample proportion, = 0.30

Significance level, = 1-0.95 = 0.05

At 95% confidence level, the critical value of Z is

Z/2 = Z0.05/2 = 1.96....( from z table)

A 95% confidence interval for the proportion of college students who say they own their cars :

Therefore a 95% confidence interval for the proportion of college students who say they own their cars is (0.2598, 0.3402)....( rounded to 4 decimal place)