12 taps flowing at the same rate can fill up pool in 1 hour. How long will it take 5 taps to fill the same pool?

Question

12 taps flowing at the same rate can fill up pool in 1 hour. How long will it take 5 taps to fill the same pool?

Answer 1

1/r is the work_rate of each one, where r>0

the combined work_rate is 12/r, and they finish the job in 1 hour.

So 12/r = 1 ---> r = 12

So each work_rate is 1/12

That is one of them finishes 1/12 of the job per hour.

For 5 of them, the combined work_rate is 5/12, so it

will take them 12/5 hours = 2 and 2/5 hours = 2 hours and 24 minutes