-
A man travels the first part of his journey at 20 km/h and the next at 70 km/h, covering the entire journey at an average speed of 50 km/h. What is the ratio of the distance that he covered at 20 km/h to that he covered at 70 km/h?
-
- 4 : 21
- 3 : 22
- 1 : 4
- 3 : 5
Correct Option: A
x/20 + y/70 = (x + y)/50
⇒ (70x + 20y)/1400 = (x + y)/50
⇒ 42x = 8y
⇒ x/y = 4/21
