What the smallest measure?

How do you find principle and simple interest

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. ?

Jaxon has s packs of 8 crazy straws. he divided the crazy straws into 2 equal bags. now, he has 224 crazy straws in each bag. how many packs of crazy straws did jaxon start with?