Question 582260
walking speed = x
cycle speed = 4x

distance = 12 miles

time walking + time cycling = 5 hours

12/x + 12/4x= 5

12/x + 3/x= 5

15/x=5
x= 15/5
x=3 miles  / hour walking speed
4x= 4*3 = 12 mph cycling speed

He walked for 12/3 = 4 hours
he bicycled for 12/12 = 1 hour.

I think you have to change the question.