A person walks at 5 km/h. If he increases his speed to 8 km/h, he takes 30 minutes less to cover a distance. What is the distance?
Show answer & explanation
Correct answer: C
Explanation
Given:
First speed = 5 km/h
Second speed = 8 km/h
Time difference = 30 minutes = 1/2 hour
Formula:
Time = Distance / Speed
Let distance = x km
x/5 − x/8 = 1/2
(8x − 5x) / 40 = 1/2
3x / 40 = 1/2
3x = 20
x = 20/3
Distance = 6.67 km