Sometimes its possible to take a hard SAT math problem and make a much simpler problem like it, with the same basic features, to get the idea of how a problem should work out. For instance:
If we subtract 1 from any of the following numbers, which will cause the greatest decrease in the answer?
23×88 x 90×107 x 114
OWCH! Tough stuff!
So make a model of it like this:
2×3 x 4—same basic idea, but much easier to deal with:
2×3 x 4 = 24
(2-1) x 3×4 = 12
2×3 x (4-1) = 18. So actually subtracting 1 from the smallest number in the sequence gives the greatest change in the answer. So back in the harder question, the smallest number (23) is probably also the one to pick.
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