Question

According to a 2009 Reader's Digest article, people throw away approximately 18% of what they buy at the grocery store. Assume this is the true proportion and you plan to randomly survey 250 grocery shoppers to investigate their behavior. What is the probability that the sample proportion is between 0.07 and 0.15?

Note: You should carefully round any intermediate values you calculate to 4 decimal places to match wamap's approach and calculations.

Answer =  (Enter your answer as a number accurate to 4 decimal places.)

Answer 1

Let denotes the sample proportion for a sample of 250 grocery shoppers.

or

Now,

The probability that the sample proportion is between 0.07 and 0.15