a pool can be filled by one pipe in 2 hours and by a second pipe in 5 hours. how long will it take using bothpipes to fill the pool?

Answer 1

Let t = time working together

time together/time alone + time together/time alone = 1

t/2 + t/5 = 1

Multiply by 10

5t + 2t = 10

7t = 10

t = 1.43 hours