⅓ x 27 in a simplest form

Name the most appropriate metric unit for each measurement

Negative 5 1/12 + negative 4 1/4 + 6 3/4

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. ?