A takes 4 h more than the time taken by B to walk D km. If A doubles his speed, he can make it in 2 h less than that of B. How much time does B require for walking D km?

Options

A. 8H
B. 4H
C. 6H
D. 9H

Answer

To solve the problem step by step, we can start by defining the variables and setting up the equations based on the information given in the question.

### Step 1: Define Variables
Let:
- \( T \) = time taken by B to walk \( D \) km
- \( S_B \) = speed of B
- \( S_A \) = speed of A