A boy walks 5 ķm at vkm/hr. He then cycles 15 km at 2v km/hr. In terms of v, write down the time taken in hours 1. When walking
2. If the total time for journey is 2h 35min, find the boy's walking speed

The time when walking is 5/v hours

The walking speed is 4 26/31 km/hr

Step-by-step explanation:

Mathematically;

time = distance/speed

So the time taken when walking will be;

5/v

The time taken when cycling will be:

15/2v

The term 2h 35 minutes is same as 2 35/60

= 2 7/12

If we add the whole times together, we get 2 7/12

Thus;

5/v + 15/2v = 2 7/12

5/v + 15/2v = 31/12

(10 + 15)/2v = 31/12

25/2v = 31/12

12 * 25 = 2v * 31

31v = 6 * 25

v = 150/31

= 4 26/31

after simplifying it i got: -36.25 as my answer. hope that !