Question

A car speed is 40 km/h in 15 minutes and then 60 km/h in next 15 minutes. Find the total distance

Answer 1

Speed = Distance ÷ time. — 1

Average speed = Total distance travelled ÷ total time taken

Part 1

Speed (v) = 25 km/h

Distance =?

Time = 30 minutes

But time is in hours,

Therefore, time = 0.5 hours

Applying the values in equation 1

25 kmph = distance ÷ 0.5 hours

Distance = 25 kmph x 0.5 hours

Distance = 12.5 km

Part 2

Speed = 40 kmph

Time = 1/3 hours

Putting the values in equation 1

40 kmph = distance ÷ 1/3 hours

Distance = 40 kmph x 1/3 hours

Distance = 13.67 km

Average speed = 12.5 km +13.67 km ÷ 0.8 hours

Average speed = 26.17 km ÷ 0.8 hours

Average speed = 32.7152 kmph