Three hoses work to fill a tub at at different rate. Hose Q and B, working together, can fill the tub in 6/5 of an hour. Hoses Q and C can fill it in 3/2 an hour. Houses B and C can fill it in 2 hours. How long does it take all 3 hoses, working together, to fill the tub?
Edited for accurate solution Choose the correct choice from the following choices:
A) 3/10
B) 2/5
C) 1/2
D) 1
E) 6/5
Convert the given time to rate and you will be able to add it up.   Total Rate of Q and B = Rate of Q + Rate of B = 1/(6/5) = 5/6   Total Rate of Q and C = Rate of Q + Rate of C = 1/(3/2) = 2/3   Total Rate of B and C = Rate of B + Rate of C = 1/2   Adding all three,   2(Rate of Q + Rate of B + Rate of C) = 5/6 + 2/3 + 1/2= 
<gadget id="calculator">5/6 + 2/3 + 1/2</gadget>
<output>2</output>
2   Rate of Q + Rate of B + Rate of C= 1 tub/hour   Time taken by all three together to fill up the tub is 1 hour=1
<result>D</result>
Three hoses work to fill a tub at at different rate. Hose Q and B, working together, can fill the tub in 6/5 of an hour. Hoses Q and C can fill it in 3/2 an hour. Houses B and C can fill it in 2 hours. How long does it take all 3 hoses, working together, to fill the tub?
Edited for accurate solution