Math problem on normal distribution

Question

A calculus exam that was taken by 116 students is recorded and normally distributed. The mean score on the exam is 76.5 and the standard deviation is 1.6. What percent of the scores are in the 73.3 and 79.7 range?

Answer 1

73.3 is 2 standard deviations below the mean 76.5 - 2(1.6)

79.7 is 2 standard deviations above the mean 76.5+2(1.6)

In a normal distribution, 95% of scores are within 2 standard deviations of the mean