Question

Tanaya cover a part of journey at 60km/h and the balance to 40km/h taking a total of 5 hours to cover a distance of 240 km.For how many hours did he drive at 40 km/h​

Answer 1

Answer:

3 hours

Step-by-step explanation:

let the distance covered ( when Tanaya driving at 60km/h) be X.

so, the distance covered ( when Tanaya driving at 40km/h ) is 240-X.

now, time taken to cover distance at 60km/h

t1 = X/60

and time taken to cover distance at 40km/h

t2 = 240-X/40

A.T.Q

t1 + t2 = 5 hours

X/60 + 240-X/40 = 5

2X + 720 - 3X/120 = 5

2X + 720 - 3X = 5 x 120

-X + 720 = 600

-X = 600 - 720

-X = - 120

X = 120

so distance covered at 60km/h is 120km

and distance covered at 40km/h is 240-120 = 120

now, hours he drive at 40km/h(time taken to cover distance at 40km/h) = 120/40

= 3 hours