I heard that on a radio show last week or something they were talking about SAT tips, and the guy that wrote the book was talking about what is greater, 34x37 or 35x36 - he wrote the book, but he didn't come up with the way to figure it out that is really the way to do it I would say, and not only that, but this way you get more info - that 35x36 is 2 more than 34x37 and actually that any number like that, n(n+3) is 2 less than (n+1)(n+2). The way you figure it out is just like that, use a variable! Set n to 34, so 34x37 is n(n+3) -> multiply out to get n squared + 3n. And 35x36 is (n+1)(n+2) -> multiply out to get n squared + 3n + 2 --> 2 more!! The callers didn't get that either. And the author of the book was repeatedly saying you can't say necessarily that that works for all the numbers like 1x4 vs 2x3, or 2x5 vs 3x4, etc. (which they all do, as you can tell by this proof), lol.

Good tip!