Hose A can fill a swimming pool in 2 hours If hose B can fil

Hose A can fill a swimming pool in 2 hours. If hose B can fill the same pool in 6 hours, how many hours will it take the hoses to fill the pool if they work together?
(A) .5 (B) 1 (C) 1.5 (D) 1.75 (E) 2

Let t = hours it takes for both working together
then
t(1/2 + 1/6) = 1
Multiplying both sides by 6:
t(3 + 1) = 6
4t = 6
t = 6/4
t = 3/2
t = 1.5 hours