An empty swimming pool can be filled by two hoses. Hose A can fill it in 6 hours and hose B can fill it in 8 hours. How many hours will it take to fill the swimming pool if both hoses are used simultaneously?
I tried this problem, but I don't know if it looks correct.
$V = 6 v_A$
$V = 8 v_B$
$V = (v_A + v_B) t$
$V = \left( \frac{V}{6} + \frac{V}{8} \right) t$
$V = \frac{4V + 3V}{24} t$
$1 = \frac{7}{24} t$
$t = \frac{24}{7}$
$t \approx 3.4285 \ldots$
The question is multiple choice.
a) 3.1
b) 3.2
c) 3.3
d) 3.4
e) none of these
It seems that, from what I calculated, the answer should be (e). But I am not too sure if I calculated it correctly.