I need help on solving along with the steps to solve

What are the equivalent ratios for 24/2= /3= /5.5=108/ = /15

Witch represents the inverse of the function f(x)=1/4x-12

Cody started biking to the park traveling 15 mph, after some time the bike got a flat so cody walked the rest of the way, traveling 4 mph. if the total trip to the park took 6 hours and it was 46 miles away, how long did cody travel at each speed? solve using rate times time= distance