If the capacity of tank X is less than the capacity of tank Y and both

Question

If the capacity of tank X is less than the capacity of tank Y and both tanks begin to fill at the same time, which tank will be filled first?

(1) Tank X is filled at a constant rate of 1.5 liters per minute.
(2) Tank Y is filled at a constant rate of 120 liters per hour.

ID: 700142
DS21243

yashikaaggarwal · Answer

Answer has to be E,

Statement 1: tank x fill at the constant rate of 1.5litre /minute
90litre / hour

But till what capacity it has to be filled?
Or what about Tank Y filling capacity?
(Not sufficient)

Statement 2: Tank y fill at the constant rate of
120litre / hour

But till what capacity it has to be filled?
Or what about Tank X filling capacity?
(Not sufficient)

Statement 1 and 2: x is filled at the rate of 90 litre/hour 
And y at 120 litre/hour
But,
What's the capacity of Tank X and Y
And what's the difference between their capacity.
Not mentioned.
So both statements together are not enough.

Posted from my mobile device

BrentGMATPrepNow · Answer

Given : The capacity of tank X is less than the capacity of tank Y and both tanks begin to fill at the same time

Target question :    Which tank will be filled first?

Statement 1 : Tank X is filled at a constant rate of 1.5 liters per minute.  
Since we have no information about the rate at which tank Y is filled, statement 1 is NOT SUFFICIENT

Statement 2 : Tank Y is filled at a constant rate of 120 liters per hour. 
Since we have no information about the rate at which tank X is filled, statement 2 is NOT SUFFICIENT

Statements 1 and 2 combined    
Statement 1 tells us that tank X is filled at a constant rate of   1.5   liters per minute.

Statement 2 tells us that tank Y is filled at a constant rate of 120 liters per hour
In other words, tank Y is filled at a constant rate of 120 liters per 60 MINUTES
In other words, tank Y is filled at a constant rate of   2   liters per MINUTE

We can see that  tank Y is filled  at a faster rate  that tank X is filled . 
However, since  tank Y has a  greater volume  that tank X , it's impossible to determine which tank gets filled first.

To better understand what I mean, consider these two possible cases: 
 Case a : Tank X holds   15   liters and tank Y holds   16   liters. 
 Time to fill a tank = (tank's volume)/(rate)  
So, time to fill tank X =   15  /  1.5   = 10 hours
Time to fill tank Y =   16  /  2   = 8 hours 
In this case, the answer to the target question is  tank Y is filled first

Case b : Tank X holds   1.5   liters and tank Y holds   16   liters. 
 Time to fill a tank = (tank's volume)/(rate)  
So, time to fill tank X =   1.5  /  1.5   = 1 hour
Time to fill tank Y =   16  /  2   = 8 hours 
In this case, the answer to the target question is  tank X is filled first

Since we cannot answer the  target question  with certainty, the combined statements are NOT SUFFICIENT

Answer: E

Cheers,
Brent

Kinshook · Answer

Asked: If the capacity of tank X is less than the capacity of tank Y and both tanks begin to fill at the same time, which tank will be filled first?

(1) Tank X is filled at a constant rate of 1.5 liters per minute.
Tank X is filled at a constant rate of 90 liters per hour.
Since rate of filling of tank Y is unknown 
NOT SUFFICIENT

(2) Tank Y is filled at a constant rate of 120 liters per hour.
Since rate of filling of tank X is unknown 
NOT SUFFICIENT

(1) +(2) 
(1) Tank X is filled at a constant rate of 1.5 liters per minute.
Tank X is filled at a constant rate of 90 liters per hour.
(2) Tank Y is filled at a constant rate of 120 liters per hour.
The capacity of tank X is less than the capacity of tank Y and both tanks begin to fill at the same time
But the filling rate of tank X is also less than the filling rate of tank Y 
Case 1: If capacity of tank X is 100 litres and capacity of tank Y is 120 litres.
Tank Y will be filled first
Case 1: If capacity of tank X is 90 litres and capacity of tank Y is 150 litres.
Tank X will be filled first
NOT SUFFICIENT

IMO E

NitishJain · Answer

E.

Given:
Capacity for tank X < Capacity for tank Y
which tank will be filled first X or Y. Need a Definite answer

Statement I. Rate for tank X = 1.5 L/min or 90 L/hour
we don't know the capacity for X to find time need to fill X and no details about Y to determine which will be filled first.  Insfficient  A & D gone

Statement II. Rate for tank Y = 120 L/hour
we don't know the capacity for Y to find time need to fill Y and no details about X to determine which will be filled first.  Insfficient  B gone

Lets combine: Rate for filling tansk X & Y are available but tanks' capacity is not given to find actual time.  Insufficient

Hence E.

Solenja · Answer

since we don't get any information regarding the original capacities of the tanks X and Y we can't really say the number which tank fills the first hence the answer is E

033 · Answer

I have a doubt, given everything is same, but if the rate of filling X is faster than Y and X has lesser capacity then Y, we would be getting the answer as C, since then in every case X will be filled before Y. please let me know if I am wrong

Bunuel · Answer

Yes, in this case the answer would be C.

PReciSioN · Answer

Can we say that it is not given to us if both tanks have any possible drainage also and so even in this case both statements are not sufficient?  Bunuel

Bunuel · Answer

I would interpret "(1) Tank X is filled at a constant rate of 1.5 liters per minute." to mean that the net filling rate, regardless of any draining mechanism, is consistently at 1.5 liters per minute. Hence, there's no need to consider drainage in this context.

PReciSioN · Answer

Yes, that makes sense. Thanks!

bumpbot · Answer

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If the capacity of tank X is less than the capacity of tank Y and both

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