4. Suppose x has a distribution with a mean of 70 and a standard deviation of 51. Random samples of size n = 36 are drawn.

Compute the mean and standard deviation of the distribution. (For each answer, enter a number.)

ux=

ox=

(b) Find the z value corresponding to x bar = 53. (Enter an exact number.)

z =

(c) Find P(x bar < 53). (Enter a number. Round your answer to four decimal places.)

P(x bar < 53) =