Problema Solution

If the speed of a new locomotive were 10km/h faster than that of an old model, then the journey between two stations 100km apart would be shortened by 30 minutes. Determine the speed of the newer model

Answer provided by our tutors

let speed of old model =x

New model speed  = x +10

Distance = 100km

So the equation would be 

100/x - 100/(x+10) = 1/2

x2 + 10x  -2000 =0

x = 40

newer model speed = 50 km/hr