Bunuel wrote:
If a, b, and c are positive integers, what is the value of a?
(1) a*b*c = c!
(2) a! + b! = 3
You can sort of 'cheat' your way through this one.
Notice that both statements are 'symmetrical'. In other words, you could swap all of the As and Bs around, and neither statement would change. Therefore, if you could find two values for a and b that fit with one or both of the statements, you could also swap those values and use them.
Here's a simpler example of a symmetrical problem:
Quote:
What is the value of a?
(1) ab = 10
(2) a + b = 7
1 and 10 work with the first statement, so 10 and 1 will work as well. 3 and 4 work with the second statement, so 4 and 3 work as well. A symmetrical statement isn't going to ever be sufficient for this kind of question! (Where it asks you for the value of just one of the two variables.)
The only exception would be if a and b always had to be equal. That seems unlikely, since the second statements says that a!+b! = 3; half of 3 is 1.5, and factorials can't be decimals in GMAT land.
Since you could definitely find multiple values that would work for a by just swapping a and b backwards, the answer is going to have to be E. On test day, I'd want to take the time to write it out, but if I was rushing, this would be a great guess.
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