Question 5.8

5.8 Restaurant survey.

You operate a restaurant. You read that a sample survey by the National Restaurant Association shows that 40% of adults are committed to eating nutritious food when eating away from home. To help plan your menu, you decide to conduct a sample survey in your own area. You will use random digit dialing to contact an SRS of 20 households by telephone.

  1. If the national result holds in your area, it is reasonable to use the binomial distribution with and to describe the count of respondents who seek nutritious food when eating out. Explain why.
  2. Ten of the 20 respondents say they are concerned about nutrition. Is this reason to believe that the percent in your area is higher than the national 40%? To answer this question, use software or Table C to find the probability that is 10 or larger if is true. If this probability is very small, that is reason to think that is actually greater than 0.4 in your area.