Question

on a journey of 80 kilometre A car covers the first 40 km with a uniform speed of 80 km/hour how fast it should travel in the next 40 kilometres so that an average speed of 100 kilometre/hour is maintained for the entire journey​

Answer 1

Answer:

let the required speed be x then,

average = (80+x)/2

Or, 100 = 80/2 + x/2

Or, 100 = 40+x/2

Or, 100-40 = x/2

Or, 60 = x/2

Or, x/2 = 60

Or, x = 60×2

= 120

so, the required speed is 120 km/hr

ans.

CHECK IT OUT!!