Question

In a circular race of 800 m length, Ram and Mohan starts at speeds of 25m/s and 40 m/sec, respectively,at the same time from the same point. After how much time they meet for the first time at the starting point, when running in the same direction?

• A. 136 seconds
• B. 120 seconds
• C. 152 seconds
• D. 160 seconds

Answer 1

Answer:

D. 160 seconds

They will meet at the starting point together when both complete whole laps.

Time taken for one round

• Ram:
  $\frac{800}{25} = 32 \text{ seconds}$
  

• Mohan:
  $\frac{800}{40} = 20 \text{ seconds}$
  

  Find LCM of times

  $\text{LCM of 32 and 20} = 160 \text{ seconds}$
  

  Convert to minutes

  $160 \div 60 = 2 \text{ minutes } 40 \text{ seconds}$