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Container A and Container B are initially full of water and the volumes of Container A and Container B are in the ratio 2 to 3 respectively. A third container, Container C, which is in volume the largest among the three containers, is initially 20 percent full of water. When one-half of Container A's water and one-third of Container B's water is poured into Container C, it's now 40 percent full of water. What is the ratio in the original volumes of the three containers A, B, and C respectively?
A. 1 to 2 to 4
B. 2 to 3 to 2
C. 2 to 3 to 5
D. 2 to 3 to 8
E. 2 to 3 to 10



Since the ratio of the volumes of Container A and Container B is 2 to 3, we can let the volumes of Container A be 2T and that of Container B be 3T. Now since one-half of Container A's water(=1/2 * 2T= T) and one-third of Container B's water(=1/3 * 3T = T) is poured into Container C, the total water poured into Container C is 2T. It is 20% of the Container C since it has at the beginning 20% of water and it increases to the 40% by pouring 2T of water. The original volumes of the Container C is, therefore, 10T(?:2T=100:20 ---> ?=5*2T). The ratio in the original volumes of the three containers A, B, and C is 2T : 3T : 10T = 2:3:10. So the answer is E.






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sanju09 wrote:Container A and Container B are initially full of water and the volumes of Container A and Container B are in the ratio 2 to 3 respectively. A third container, Container C, which is in volume the largest among the three containers, is initially 20 percent full of water. When one-half of Container A's water and one-third of Container B's water is poured into Container C, it's now 40 percent full of water. What is the ratio in the original volumes of the three containers A, B, and C respectively?
A. 1 to 2 to 4
B. 2 to 3 to 2
C. 2 to 3 to 5
D. 2 to 3 to 8
E. 2 to 3 to 10

The intended meaning of the phrase in red is unclear.
The phrase original volumes suggests values that can CHANGE from ORIGINAL values to NEW values: in other words, the AMOUNTS OF WATER in the three containers.
The phrase volumes of the three containers seems to refer to the CAPACITY of each container: how much water each container can hold.
The solution below presumes that the question stem is asking for the following ratio:
(capacity of A) : (capacity of B) : (capacity of C).

We can PLUG IN THE ANSWERS, which represent the ratio of the three capacities.
At the start, A is 100% full, B is 100% full, and C is 20% full.
When 1/2 of A and 1/3 of B are poured into C, the percentage of water in C increases from 20% to 40%.
In other words, the amount of water in C must DOUBLE.

Answer choice D:
Let A = 20 liters of water, B = 30 liters of water and C = 20% of 80 = 16 liters of water.
(1/2 of A) + (1/3 of B) = 10 + 10 = 20.
Since the value in red (20) will more than double the amount of water in C (16), the relative capacity of C is too small.
Eliminate D.

Answer choice E:
Let A = 20 liters of water, B = 30 liters of water and C = 20% of 100 = 20 liters of water.
(1/2 of A) + (1/3 of B) = 10 + 10 = 20.
Success!
The value in red (20) will double the amount of water in C (20).

The correct answer is E.

GMATGuruNY wrote:

sanju09 wrote:Container A and Container B are initially full of water and the volumes of Container A and Container B are in the ratio 2 to 3 respectively. A third container, Container C, which is in volume the largest among the three containers, is initially 20 percent full of water. When one-half of Container A's water and one-third of Container B's water is poured into Container C, it's now 40 percent full of water. What is the ratio in the original volumes of the three containers A, B, and C respectively?
A. 1 to 2 to 4
B. 2 to 3 to 2
C. 2 to 3 to 5
D. 2 to 3 to 8
E. 2 to 3 to 10

The intended meaning of the phrase in red is unclear.
The phrase original volumes suggests values that can CHANGE from ORIGINAL values to NEW values: in other words, the AMOUNTS OF WATER in the three containers.
The phrase volumes of the three containers seems to refer to the CAPACITY of each container: how much water each container can hold.
The solution below presumes that the question stem is asking for the following ratio:
(capacity of A) : (capacity of B) : (capacity of C).

We can PLUG IN THE ANSWERS, which represent the ratio of the three capacities.
At the start, A is 100% full, B is 100% full, and C is 20% full.
When 1/2 of A and 1/3 of B are poured into C, the percentage of water in C increases from 20% to 40%.
In other words, the amount of water in C must DOUBLE.

Answer choice D:
Let A = 20 liters of water, B = 30 liters of water and C = 20% of 80 = 16 liters of water.
(1/2 of A) + (1/3 of B) = 10 + 10 = 20.
Since the value in red (20) will more than double the amount of water in C (16), the relative capacity of C is too small.
Eliminate D.

Answer choice E:
Let A = 20 liters of water, B = 30 liters of water and C = 20% of 100 = 20 liters of water.
(1/2 of A) + (1/3 of B) = 10 + 10 = 20.
Success!
The value in red (20) will double the amount of water in C (20).

The correct answer is E.

The term 'original' used here may be redundant but leads to no confusion or presumption at all because ultimately it talks about the volume of the three containers, and not about the volumes of water they currently hold. But still, since I too feel it useless, hence it's removed now. Thanks Mitch.