Pipe A can fill a tank in 3 hours. If pipe B can fill the same tank in

Question

Pipe A can fill a tank in 3 hours. If pipe B can fill the same tank in 2 hours, how many minutes will it take both pipes to fill 2/3 of the tank?

A. 30
B. 48
C. 54
D. 60
E. 72

Archit3110 · Answer

combined rate ' 1/3+1/2 = 5/6 
time 6/5 * 60 = 72 
2/3 * 72 = 48 mins IMO B

or say
180 mins and 120 mins

1/180 + 1/120 ; 5/360 ; 72 mins 
2/3 * 72 = 48 mins IMO B

Bunuel · Answer

Sorry Archit. There was a copy/paste error. Corrected question reads:  how many minutes will it take both pipes to fill  2/3  of the tank?  Edited. Thank you.

Chethan92 · Answer

Total work to be done is LCM(2,3) = 6 units.
A can do 3 units in 1 hour.
B can do 2 units in 1 hour.
Together they can do 5 units in 1 hour.
They require 6/5 hours to fill the tank completely.
To fill 2/3 of the tank, they require 2/3*6/5*60 min = 48 min.

B is the answer.

m1033512 · Answer

IMO B .

together they can fill full tank in 6/5 hours = 72 mins .

so 2/3 tank will fill in 72*2/3 = 48 mins

Posted from my mobile device

Mrpd · Answer

Considering x as the capacity of the tank

Flow rate of pipe A per minute:  \frac{x}{(3*60)}=\frac{x}{180}

Flow rate of pipe B per minute:  \frac{x}{(2*60)}=\frac{x}{120}

Flow rate of both pipes working together:

\frac{x}{120}+\frac{x}{180}=\frac{5x}{360}=\frac{x}{72}

\frac{x}{72}*t=\frac{2*x}{3}

t=48min

Ans B

Archit3110 · Answer

combined rate = 1/3+1/2 = 5/6
so for 2/3 filling 
2/3 = 5/6 * time * 1/60 
so
time = 2*6*60/3*5 = 48
IMO B

gvij2017 · Answer

I think question is edited now. Because previously 2/3rd was written as 2323.

ScottTargetTestPrep · Answer

The rate of pipe A is 1/3, and the rate of pipe B is 1/2. We let n = the time that the two pipes work together to fill 2/3 of the tank and create the equation:
 
(1/3)n + (1/2)n = 2/3 
 
Multiplying by 6, we have:
 
2n + 3n = 4
 
5n = 4
 
n = 4/5 hour = 48 minutes
 
Answer: B

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Pipe A can fill a tank in 3 hours. If pipe B can fill the same tank in

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