A 4000 liter tank, half-full of water is being filled from a pipe with

Question

Competition Mode Question

A 4000 liter tank, half-full of water is being filled from a pipe with a flow rate of 1 kiloliter every 2 minutes. At the same time, the tank is losing water from two drains at a rate of 1 kiloliter every 4 minutes and every 6 minutes. How many minutes does it take to fill the tank completely?

A. 8
B. 12
C. 18
D. 24
E. 48

so we need 2000l to be filled.....in x minutes

going through options by solving (1000/2 -1000/4 - 1000/6)x = 2000 => x = 24

OA:D

A. 8
B. 12
C. 18
D. 24
E. 48

EncounterGMAT · Answer

Filling 1 kl - 2 minutes   => 1/2 kl - 1 minute

4000 liter tank is half full....so 2000 liters to fill => 1000 liters every minute is filled up

Losing 1 kl - 4 minutes and 6 minutes from 2 drains

=> From drain 1- 1000/4 liters = 250 liters per minute lost/minute, and from drain 2- 1000/6 liters lost/minute.

=> Total gain = (250-1000/6) = 500/6 liters per minute.

2000 liters ÷ 500/6 liters/minute =  24 minutes  - OPTION D

unraveled · Answer

A 4000 liter tank, half-full of water is being filled from a pipe with a flow rate of 1 kiloliter every 2 minutes. At the same time, the tank is losing water from two drains at a rate of 1 kiloliter every 4 minutes and every 6 minutes. How many minutes does it take to fill the tank completely?

A. 8
B. 12
C. 18
D. 24
E. 48

so we need 2000l to be filled.....in x minutes

going through options by solving (1000/2 -1000/4 - 1000/6)x = 2000 => x = 24

OA:D

A. 8
B. 12
C. 18
D. 24
E. 48

Rate of filling = 1/2 - 1/4 - 1/6 = 1/12 kl/min
Amount of water left to be filled = 4000/2 = 2000 l = 2kl

Hence time taken to fill the remaining half filled tank =  2/\frac{1}{12}  min
= 24 min

Answer (D).

eakabuah · Answer

Rate of tap= 1000/2=500/min
Rate of drain 1=1000/4=250
Rate drain 2 = 1000/6 =500/3
Effective rate of filling = 500-250-500/3 = 250/3
So if in 1 min 250/3 liters is added,
Then how many minutes, t, would it take to add 2000 liters 
t = 2000/(250/3) = 2000*3/250 = 24 minutes.

The answer is therefore D.

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madgmat2019 · Answer

A 4000 liter tank, half-full of water is being filled from a pipe with a flow rate of 1 kiloliter every 2 minutes. At the same time, the tank is losing water from two drains at a rate of 1 kiloliter every 4 minutes and every 6 minutes. How many minutes does it take to fill the tank completely?

A. 8
B. 12
C. 18
D. 24
E. 48

so we need 2000l to be filled.....in x minutes

going through options by solving (1000/2 -1000/4 - 1000/6)x = 2000 => x = 24

OA:D

A. 8
B. 12
C. 18
D. 24
E. 48

so we need 2000l to be filled.....in x minutes

going through options by solving (1000/2 -1000/4 - 1000/6)x = 2000 => x = 24
 
OA:D

Msarkar · Answer

The answer is 24 minutes.
Let's say there is a pipe A and 2 drains B and C.
A fills the tank at the rate 1/2 KL/min, B drains the tank at the rate of 1/4 KL/min and C drains the tank at the rate of 1/6 KL/min.
So, the tank is filled at the rate of 1/2-1/4-1/6 = 1/12 KL/min.
Therefore, 1KL is filled in 12 mins. 
The tank is 4000L and half full, so 2KL is filled in 24 mins.
Kudos if you like the explanation.

Verbal33 · Answer

A 4000 liter tank, half-full of water is being filled from a pipe with a flow rate of 1 kiloliter every 2 minutes. At the same time, the tank is losing water from two drains at a rate of 1 kiloliter every 4 minutes and every 6 minutes. How many minutes does it take to fill the tank completely?

A. 8
B. 12
C. 18
D. 24
E. 48

so we need 2000l to be filled.....in x minutes

going through options by solving (1000/2 -1000/4 - 1000/6)x = 2000 => x = 24

OA:D

We have to fill half tank i.e. 2000 ltr
Lets take LCM of 2, 4, and 6 = 12

So we can say that
Pipe 1: fills tank 6 kiloliter in 12 min
Pipe 2: empties 3 kiloliter in 12 min
Pipe 3: empties 2 kiloliter in 12 min

In 12 min the tank fills 1 kiloliter

Therefore to fill 2000 liter it will take 24 min.

Answer: D

nishthagupta · Answer

4000 L tank - 2000 L tank needs to be filled. 
2000L = 2Kl
inflow speed-outflow speed=speed with which tank is filled
1/2-1/4-1/6=1/12

1 min<--1/12Kl
12 mins<-- 1 kl
24mins<--- 2 Kl

Archit3110 · Answer

net flow rate; 1/2-1/4-1/6 ; 1/12
so for 2000 ltrs time taken ; 2000/1000*12 ; 24 mins
IMO D

A 4000 liter tank, half-full of water is being filled from a pipe with a flow rate of 1 kiloliter every 2 minutes. At the same time, the tank is losing water from two drains at a rate of 1 kiloliter every 4 minutes and every 6 minutes. How many minutes does it take to fill the tank completely?

A. 8
B. 12
C. 18
D. 24
E. 48

so we need 2000l to be filled.....in x minutes

going through options by solving (1000/2 -1000/4 - 1000/6)x = 2000 => x = 24

OA:D

A. 8
B. 12
C. 18
D. 24
E. 48

exc4libur · Answer

capacity:  4000L = 4KL 
time to fill:  \frac{4}{1/2-(1/4+1/6)}=\frac{4}{1/2-(5/12)}=\frac{4}{1/12}=48

Answer (E)

StressTest · Answer

D: 24

Rate of loosing = 1/4 + 1/6 => 5/12KL/M
Rate of filling = 1/2 KL/M

2= 1/2*t-(5/12)*t
t=24

bumpbot · Answer

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A 4000 liter tank, half-full of water is being filled from a pipe with

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