Imagine that you are taking a test that consists of two questions. After your
teacher hands out the test, and before you set to work, a helpful little gnome
whispers to you, “The first problem is very simple, the second is much harder.”
Would the gnome’s statement affect the way you approach the two problems? Yes.
For a “very simple” question, it seems likely that you should be able to answer
it quickly and with little or no agonized second-guessing. You will probably
have to spend much more time on a “much harder” question, both to come up with
an answer and to check your work to make sure you didn’t make an error somewhere
along the way.
What about all the other students who didn’t hear the gnome? They might labor
over the first, easy question, exhaustively checking their work and wasting time
that they’ll need for the tricky second problem. Then, when those other students
do get to the second problem, they might not check their work or be wary of
traps, since they have no idea that the problem is so difficult.
The moral here is you should spend less time on the simpler questions that
appear early in the test, and devote more time to the harder questions appearing
later. Because Math IC questions are ordered by difficulty, it’s as if you have
that helpful little gnome sitting next to you for the entire test.