Hi Bryan,

Yes, Choice A is the 'eye-catcher.' When most people cannot solve a problem, they choose the answer that seems right. But if this were the answer, most students would answer the question correctly and therefore it would not perform as a hard question.

Nova Press

Hi Bryan,

Good question: How do we know when a problem is hard?

Exact criteria cannot be given for what makes a problem hard.

It's not based on complexity. There really are no complex problems on the GRE. Even the hard problems are simple, but they are subtle.

As you study GRE problems, you will develop some intuition for the difficulty level of the problems. The exotic nature of this particular problem is a tip off that it is hard.

The purpose of these hard-problem strategies is usually not to solve the problem (though that can occur), rather their purpose is to prevent making an error. If you could not solve the problem, then you should not guess choice (A) because it is too obvious. And if you did solve the problem and got (A) as the answer, then you should check your work for errors and any unwarranted assumptions you may have made.

We solved the problem mathematically by analyzing the equation 4x = (2^2)x and the fact that x is given to be even.

Nova Press

Its true ,any of even num has one prime factor which is 2 and in example here its given by 4=2*2.so any of way its become a common.

Hello Wendy. Two critical information pieces: 1) x is even, and 2) 4 has 2 as its distinct prime factor, in addition to whatever x has as distinct prime factors.

Since x is even, we conclude that 2 is one of its prime factors (e.g., 6 has 2 and 3. 36 has 2, 3, and 9, etc.). Hence having 4 as a multiplier in Column A does not add any additional distinct prime factor to those of x.

The answer then, is C.

Hi Arushi,

We cannot choose x to equal 1 because 1 is an odd number, and we are told that 'x is an even integer.'

Nova Press