Water started leaking from a tank yesterday at 12:00 noon at a constan

Question

Water started leaking from a tank yesterday at 12:00 noon at a constant rate of 0.5 ounce per second and continued leaking at this rate until the tank was empty. If the tank was empty at 8:00 yesterday evening, which of the following was the amount of water in the tank, in ounces, yesterday at 12:00 noon?

A. 1,280
B. 6,480
C. 10,240
D. 14,400
E. 15,360

A. 1,280
B. 6,480
C. 10,240
D. 14,400
E. 15,360

gladkian · Answer

A=RT
R=A/T

Rate at which the water is flowing out:

1) Convert 0.5 ounce/sec into minutes = 0.5*60/1*60 (seconds) = 30/60 seconds (or 1 minute). Therefore, R = 30 ounces / 1 minute.
2) 30/1 = X/480 (since the tank was empty at 8PM, convert 8 hours into minutes by 8*60)
3) 30*480 = 14,400

ScottTargetTestPrep · Answer

Recall that there are 3600 seconds in one hour; thus, in 8 hours, we have 3600 x 8 seconds. We can create the equation:

0.5 x 3600 x 8 = n

14,400 = n

Answer: D

Harsh020 · Answer

For this question, and for other similar questions, do we assume that the tank was full when it started leaking?

Bunuel · Answer

The question does not ask for the tank’s capacity. It asks for the amount of water that was in the tank at 12:00 noon, which is simply the amount of water present in the tank when the leak began. That amount may or may not have been the tank’s full capacity, but for this question we are not given, and do not need, the tank’s capacity.

egmat · Answer

Hi Harsh020,

Great question! The short answer is:  No , we do  NOT  assume the tank was full.

The question never mentions the tank's total capacity. It only tells us:
- Water started leaking at  12:00  noon
- It leaked at  0.5  ounces per second
- The tank was empty by  8:00 PM

Since ALL the water leaked out between noon and  8 PM , the total water that leaked out equals however much water was in the tank at noon — whether the tank was full, half-full, or one-third full doesn't matter.

Here's the calculation: 
- From  12:00  noon to  8:00 PM  =  8  hours
-  8  hours =  8  ×  60  ×  60  =  28,800  seconds
- Water leaked =  0.5  ×  28,800  =  14,400  ounces

So there were  14,400  ounces in the tank at noon. That's all we know. The tank's maximum capacity could have been  14,400  ounces (full) or  100,000  ounces (barely filled) — the question doesn't care about that.

General principle:  In these problems, focus only on what's stated. If the problem says water leaked until the tank was empty, then: Amount at the start = Total amount leaked. No assumptions about 'full' or 'capacity' are needed.

Answer: D

Fucio · Answer

The amount of time the tank spent leaking is from 12:00 noon to 8:00 pm so it's 8h total.

8h equals 8*60 = 480 minutes, which again equals 480*60 =28,800 seconds

Since the tank leaks at 0.5 ounces per second and at the end of the time period the tank was full the amount of water leaked (i. e. the amount of water at the beginning) is 28,800*0,5 which is half 28,800 so 14,400.

The answer choice is D

Water started leaking from a tank yesterday at 12:00 noon at a constan

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