3 Questions - 1: A set of math tests is normally distributed with a mean of 81 and a standard deviation of 5. If Adam’s z-score was -0.6 and Leah’s z-score was 2.2, how many points higher did Leah score than Adam?

2: The number of homes sold each year by a realtor is normally distributed with a mean of 54. If the realtor sold 36 homes last year with a z-score of -2.4, what is the standard deviation?

3: The 400-meter race times recorded in the boys track meet was normally distributed with a standard deviation of 3 seconds. If David finished the race in 51.2 seconds with a z-score of -2.6, what was the mean time?