Question

A police car passed a truck which was traveling at 80km/h and 6 minutes (1/10 hour) later was 3 km ahead of the truck. What was the speed of the police car?

Answer 1

Speed of Police Car = 110 km per hr

Explanation:

Speed of Truck S(t) = 80 km p h

Distance = speed x time

Hence distance covered by truck in
`(1)/(10)` hours

`\ D(t)= \ S(t) *  (1)/(10)`

`\ D(t)= 80 * (1)/(10)`

D(t)=8 km

Distance covered by police car = 3 km more than that of Truck

D(c) = 8+3=11 km

Time taken =
`(1)/(10) hours`

Speed =
`(\ Distance )/(\ time)`

Replacing those values

Speed =
`(11)/((1)/(10))`

Speed =
`11 * 10`

Speed = 110 kmph