Question

a walks 4 m per second and b walks 7.2 kilometre per hour they started together from the same p place to add the same direction how many metres apart will they be after 40 minutes

Answer 1

a walks 860m and b walks4.8km

Answer 2

A walks with velocity of 4m/s
That is 14.4km/h

B walks with the speed of 7.2km/h

After 40min
A would have travelled - 14.4 * 0.66 = 9.504 km.

And B would have travelled - 7.2 * 0.66 = 4.752km
Hence they would be
$4.75 \: km$
away.