On a test that has a normal distribution, a score of 28 falls two standard deviations above the mean, and a score of 22 falls one standard deviation below the mean. Determine the mean of this test.

It took alice 5 5/6 hours to drive to her grandparents' house for . on the way home, she ran into traffic and it took her 7 3/8 hours. how much longer did the return trip take? write your answer as a proper fraction or mixed number in simplest form. the trip home took __hours longer. ?