Question

The shortest route from London to York is 200 miles.

A lorry is expected to take 4 hours to travel this route.
The lorry actually travels by a different route which increases the distance by 20%, but it still arrives in 4 hours.
By how many more mph than the expected speed does the lorry travel?

Answer 1

Answer: The lorry is traveling 10 mph over the expected speed.

Explanation:

If 200 miles takes 4 hours, the speed is 200mi/4hr which is 50 mph.

If the distance is increased by 20%, the distance is 240 miles.

240mi/4hr = 60mph

The difference is 10mph