Question

A boy covers a distance of 25km in 4h partly on foot at the rate of 3.5kmph and partly on cycle at 9kmph. Find the distance covered on foot.

Answer 1

Let x be the time taken on foot
then, 4-x will be the time on cycle


therefore

x*3.5+ (4-x)*9 = 25
3.5x + 36 -9x= 25
9x-3.5x=36-25
5.5x=11
x=11/5.5
x= 2 hrs

therefore distance on foot
distance =2*3.5=7km