Question

A car moves with a speed of 40 km/h for 15 minutes and then with a speed of 60 km/h for the next 15 minutes .What is the total distance covered by the car?

Answer 1

For the first part of journey,

Speed=40km/h and time=15min=1/4 hour

Using ,speed=distance/time

Distance=40 x 1/4=10km

For the second part of journey,

Speed=60km/h and time=15 min=1/4 hour

Then distance=60 x 1/4=15 km

Total distance travelled in whole journey=10+15=25 km

Answer 2

Speed for first 15 minutes = 40km/h Now 15 minutes= 15/60 hours Distance1 = Speed × Time = 40 × 15/60 = 10 km Speed for last 15 minutes = 60km/h Now 15 minutes= 15/60 hours Distance2 = Speed × Time = 60 × 15/60 = 25 km Now total distance covered = distance1 + distance2 = 10 km + 25 km = 35 I'm  Answer) 35 km