Einstein walk in an escalator at a rate of 5 steps per second and reaches the other end in 10 seconds. While coming back, walking at the same speed he reaches the starting point in 40 seconds. What is the number of steps on the escalator?

Options

A. 40
B. 60
C. 120
D. 80

Answer

To solve the problem step by step, we will use the information provided about Einstein's movement on the escalator.

### Step 1: Define Variables
Let:
- \( n = 5 \) steps per second (Einstein's walking speed)
- \( b \) = speed of the escalator in steps per second
- \( L \) = total number of steps on the escalator