# stats questions

1. A random sample of size n = 175 is taken from a population with population proportion P = 0.71.

Calculate the expected value and the standard error for the sampling distribution of the sample proportion.(Round intermediate calculations to 4 decimal places, “expected value” to 2 decimal places and “standard deviation” to 4 decimal places.)

exptected value?

2.Suppose that the miles-per-gallon (mpg) rating of passenger cars is a normally distributed random variable with a mean and a standard deviation of 31.9 and 3.4 mpg, respectively.

 a. If two passenger cars are randomly selected, what is the probability that all of the passenger cars get more than 34 mpg? (Round intermediate calculations to 4 decimal places, “z” value to 2 decimal places, and final answer to 4 decimal places.)probability?

 b. What is the probability that a randomly selected passenger car gets more than 34 mpg? (Round intermediate calculations to 4 decimal places, “z” value to 2 decimal places, and final answer to 4 decimal places.)probability?