The Mean Length of Time, Per Week, That Students at a Certain

Multiple Choice

The mean length of time, per week, that students at a certain school spend on their homework is 24.3 hours, with a standard deviation of 1.4 hours. Assuming the distribution of study times is Normal, what percent of students study between 22.9 and 25.7 hours?

A) 99.7%
B) 95%
C) 68%
D) 50%