Question

A cyclist moves non-stop from a to b, a distance of 52 km, at a certain average speed. if his average speed reduces by 1 km per hour, he takes 20 minutes more to cover the same distance. the original average speed of the cyclist is

Answer 1

let his original average speed be x km per hour
time taken=52/x
new speed=x-1
new time=52/(x-1)
52/(x-1)-20/60=52/x

${x}^{2} - x - 156 = 0$
x=13