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

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
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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

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

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.
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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

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