Question 934559
a) calculate z-score for 590
z-score = (590 - 508) / 113 = 0.725663717  approx 0.73
Pr(X<590) = 0.7673
b) Pr(X>525) = 1 - Pr(X<525)
calculate the z-score for 525
note that the sample size is 1200 > 40, so we can use the population standard deviation
z-score = (525 - 508) / 113 = 0.150442478 approx 0.15
Pr(X>525) = 1 - Pr(X<525) = 1 - 0.5596 = 0.4404