Question

Tom drives a truck. His regular trip is a distance of 280 km. He drives at an average speed of 80 km/h.

For safety reasons Tom’s boss puts a speed limiter on his truck. This reduces Tom’s average speed by 10 km/h.

How much longer will it take Tom to drive his regular trip?

Answer 1

.5 hour, or 30 minutes

Explanation:

280 km / 80 kmh = 3.5 hr before limiter

280 km / (80-10) kmh = 4 hr after

so .5 hour from 3.5 to 4 hours. or 30 minutes

This is provided he matains this speed at all times.