Question

A person completed a distance of 75 km in 7 hour .he travelled some distance at 12km/h and rest distance at 10 km/h.how much distance did he travel at 12 km/hr

Answer 1

Let the distance travelled at the rate of 12 kmph be x km
Time taken to travel this distance = x/12 .......(1)
Then the distance travelled at the rate of 10 km/hr will be 75 – x
Time taken to travel this distance = (75 – x)/10 .......(2)
Total time taken to cover the total distance = 7 hrs
⇒ (x/12) + (75 – x)/10 = 7 [sum of (1) and (2)]
⇒ 10x + 900 – 12x = 840
⇒ –2x = –60
⇒ x = 30.
Therefore, the distance travelled at the rate of 12 km/hr = 30km.

Answer 2

Step-by-step explanation:

(d/12+(75-d/10) = 9

now solve it