Question

a motor bike starts at the speed of 60kmph with the speed increasing by 12 kmph every three hours. In how many hours will cover 480km​

Answer 1

Answer:

7 hours

Step-by-step explanation:

First 3 hours : 180 km covered ( 60 * 3)  

Second 3 hours : 216 km covered (72 * 3)  (60 + 12 = 72)

Total Distance : 396.

After this, the speed becomes 84 km/h, so distance in 1 hour = 84. (72 + 12)

Total distance  (current) : 396 + 84 = 480.

Total time = (first 3 hours) + (second 3 hours) + 1 extra hour ( when it changes to 84 kmph)

                 = 3 + 3 + 1  == 7

Hope it helps..