A swimming pool holds 585,000 liters of water. The pool has two drainage pipes. When the pool is completely full, the first pipe alone can empty it in 135 minutes, and the second pipe alone can empty it in 195 minutes. When both pipes are draining together, how long does it take them to empty the pool?

79.77 minutes

Step-by-step explanation:

first you have to find out how many liters the pipes drain per minute

pipe 1: 585000/135=4333.33 lpm

pipe 2:585000/195=3000 lpm

p 1 and 2: 7333.33 lpm

now divide the lpm of both pipes by the amount in the pool to find your answer

585000/7333.33=79.77 minutes

-2 is the right

here is your mark brainliest