The Amount of Time Workers Spend Commuting to Their Jobs

Multiple Choice

The amount of time workers spend commuting to their jobs each day in a large metropolitan city has a mean of 70 minutes and a standard deviation of 20 minutes. Assuming the distribution of
Commuting times is known to be moundshaped and symmetric, what percentage of these
Commuting times are between 50 and 110 minutes?

A) approximately 81.5%
B) approximately 68%
C) approximately 97.5%
D) approximately 95%