GmatGreen wrote:During the 2nd quarter of 1984, a total of 2,976,000 domestic cars were sold. If this was 24 percent greater than the number sold during the first quarter of 1984, how may were sold during the first quarter?

A) 714,240
B) 2,261,760
C) 2,400,000
D) 3,690,240
E) 3,915,790

I get intimidated by these questions and panic without a calculator. Time saving tips?

We know that 2,976,000 is 24% GREATER THAN the correct answer choice.
Answer choices D and E are both greater than 2,976,000, so we can ELIMINATE them.
Answer choice A is far too small. 2,976,000 is more than 300% greater than 714,240. So, ELIMINATE A.

This leaves us with either B or C.
C is nicer to work with, so let's test it first.
Is 2,976,000 24% greater than 2,400,000?
Well, 25% (aka 1/4) of 2,400,000 is 600,000
If we add 600,000 to 2,400,000, we get 3,000,000 (which is CLOSE to 2,976,000)
From here, we can assume that since 24% is a LITTLE LESS than 25%, then a 24% increase would result in a value a LITTLE LESS 3,000,000 (perfect - is a 2,976,000 LITTLE LESS than 3,000,000)

So, the correct answer is C

Cheers,
Brent