If Osvaldo and Clair can clean a pig trough in eight hours working together, and Clair can clean it two hours faster than Osvaldo, how long will it take Osvaldo to clean the pig trough by himself? Round your answer to the nearest tenth.

Solution:

Clair: x

Osvaldo: x+2

So

1/x+1/(x+2) = 1/8

So

x=15.0

So it takes Osvaldo 17.0 hours to clean the pig trough by himself