Question

A motorist travelled from Town A to Town B which was 40 km apart, at an average speed of
x km/h.
(a) Write down an expression for the time, in hours, that he took for the journey.
(b) He returned by the same route but at an average speed that was 20 km/h less.
Write down an expression for the time, in hours, that he took for the return
journey.
(c) Given that the difference between his two times was
15
8 hour, form an
equation in x and show that it reduces to x2- 20x -1500 =0 .
(d) Solve this equation and find
(i) his initial average speed,
(ii) the time taken, in hours and minutes, for the return journey.

Answer 1

I don't know this answer so I hope you don't mind it.