1)In a recent year, the Better Business Bureau settled 75% of complaints they received. (Source: USA Today, March 2, 2009) You have been hired by the Bureau to investigate complaints this year involving computer stores. You plan to select a random sample of complaints to estimate the proportion of complaints the Bureau is able to settle. Assume the population proportion of complaints settled for the computer stores is the 0.75, as mentioned above. Suppose your sample size is 277. What is the probability that the sample proportion will be at least 5 percentage points higher than the population proportion?

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

2)Business Weekly conducted a survey of graduates from 30 top MBA programs. On the basis of the survey, assume the mean annual salary for graduates 10 years after graduation is 168000 dollars. Assume the standard deviation is 39000 dollars. Suppose you take a simple random sample of 58 graduates. Assume the population is normally distributed.

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

Find the probability that a single randomly selected salary exceeds 160000 dollars. P(X > 160000) = Enter your answer as a number accurate to 4 decimal places. Find the probability that a sample of size n=58n=58 is randomly selected with a mean that exceeds 160000 dollars. P(xx > 160000)

3)A particular fruit's weights are normally distributed, with a mean of 317 grams and a standard deviation of 15 grams. If you pick one fruit at random, what is the probability that it will weigh between 299 grams and 320 grams?

(If you get two values that are the same, please regenerate the problem or contact the instructor if you are unable to do so.)

Answer =

4)A set of exam scores is normally distributed and has a mean of 73.8 and a standard deviation of 7.7. What is the probability that a randomly selected score will be between 72 and 77?

Answer =

5)Suppose the true proportion of voters in the county who support a restaurant tax is 0.6. Consider the sampling distribution for the proportion of supporters with sample size n = 184. What is the mean of this distribution? (Enter your answer accurate to two decimal places.) What is the standard deviation of the sampling distribution (i.e. the standard error)?