It takes an inlet pipe of a small swimming pool 20 minutes less to fill the pool than it takes an outlet pipe of the same pool to empty it. through an error, starting with an empty pool, both pipes are left open and the pool is filled after 4 hours. how long does it take the inlet pipe to fill the pool and how long does it take the outlet pipe to empty it?

It takes the inlet pipe 60 minutes or 1 hour to fill the pool and takes the outlet pipe 80 minutes or 1.33 hours to empty the pool

Step-by-step explanation:

Please kindly check the attached files for details.

the answer is c hope this

  or  

sin y = 7/q

7 is the opposite side length, q is the hypotenuse

tan y = 7/r

7 is the opposite side length, r is the adjacent side length

using sohcahtoa ^^^^

cos y = adjacent/hypotenuse

cos y = r/q