When to use VIC method

[Guest]

From Word Translation Question Bank

Would this be a good candidate for VIC?

Also, this seems awfully difficult to be on the actual test... or maybe I just need a lot more work. But either way, it takes too long for me to work this out:

Reserve tank 1 is capable of holding z gallons of water. Water is pumped into tank 1, which starts off empty, at a rate of x gallons per minute. Tank 1 simultaneously leaks water at a rate of y gallons per minute (where x > y). The water that leaks out of tank 1 drips into tank 2, which also starts out empty. If the total capacity of tank 2 is twice the number of gallons of water actually existing in tank 1 after one minute, does tank 1 fill up before tank 2?

(1) zy < 2x^2 - 4xy + 2y^2

(2) The total capacity of tank 2 is less than one-half that of tank 1.

When I used VIC, I was able to actually come up with an answer without any of the statements. I know I must have gone wrong somewhere, but I am not sure how to tackle something like this in the future.

Wht's the key takeaway here? D=RT? I am not able to apply what I learned from here to another similar question. Huge issue for me. How do I "see throug" what they are asking??

[RonPurewal]

From Word Translation Question Bank

Would this be a good candidate for VIC?

Also, this seems awfully difficult to be on the actual test... or maybe I just need a lot more work. But either way, it takes too long for me to work this out:

Reserve tank 1 is capable of holding z gallons of water. Water is pumped into tank 1, which starts off empty, at a rate of x gallons per minute. Tank 1 simultaneously leaks water at a rate of y gallons per minute (where x > y). The water that leaks out of tank 1 drips into tank 2, which also starts out empty. If the total capacity of tank 2 is twice the number of gallons of water actually existing in tank 1 after one minute, does tank 1 fill up before tank 2?

(1) zy < 2x^2 - 4xy + 2y^2

(2) The total capacity of tank 2 is less than one-half that of tank 1.

When I used VIC, I was able to actually come up with an answer without any of the statements. I know I must have gone wrong somewhere, but I am not sure how to tackle something like this in the future.

Wht's the key takeaway here? D=RT? I am not able to apply what I learned from here to another similar question. Huge issue for me. How do I "see throug" what they are asking??

you can't use the straight vic method for data sufficiency problems, because the entire vic method is predicated on checking your work against answer choices. if you don't have answer choices, you can't use the vic method, except in rare cases in which the answer is a constant (such as "by what factor does this quantity grow...?")
i'd be interested in seeing how you tried to plug numbers into this problem.

not that you CAN'T plug numbers in data sufficiency problems; it's just a different KIND of number plugging. because the goal is to determine whether a statement is sufficient or insufficient, you MUST plug in multiple numbers (or multiple sets of numbers, if there's more than one unknown in the problem).

in any case, what sort of number plugging did you try? maybe we could help you turn that number plugging in a better direction.