Question

Anita can clean a typical pool in 8 hours. Chao can clean a typical pool in 6 hours. How long should it take Anita and Chao working together to clean a typical pool?

Answer 1

This kind of problems requires to add the working velocities. The total velocity is the sum of the individual velocities.

Anita's velocity = 1 pool/8 hours
Chao's velocity = 1 pool/6 hours

Combined velocity 1/8 + 1/6 = (3 + 4)/24 = 7/24 pool/hour

Time = 1 pool / (7/24) pool/hour = 24/7 hour =3.43 hours