Normal Distribution

Question

The scores on an entrance exam to a university are known to have approximately normal distribution with a mean 65% and standard deviation 7.1%. what percentage of students would score 70 or better on this entrance exam

Answer 1

Prob( X>70) = 1 - Prob(x<70) = 1 - Prob( (70-65)/7.1) = 1 - Prob ( z < 0.7042553) = 0.24065 = 24.065%