A plumber laying 500meters of drain pipe requires 20men working for 10days. What length in meters would be laid by 50men in 5days, if they all work at same rate?

50men working in 5days will lay 100 meters

Step-by-step explanation:

If 20men working for 10days lays 500meters

then, 1 man will lay 10,000 meters in 10 days

also, 1 man will lay 1000 meters in 1 day

If 1 man lays 1000 meters in 1 day,

Then, 50 men will lay (1000 meters / 50); 20 meters in 1 day

also, the same 50 men will lay (20 meters x 5days); 100 meters in 5 days.

Therefore, 50men working in 5days will lay 100 meters