How many digit (0,1,2,3,4,5,6,7,8,9) sequences of length 9 are there that contain at least 4 odd digits (1.3.5.7.9) and at least 4 even digits (0,2,4,6,8)

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. ?