We've gotta be prepared for GIA (also known as ACT in America) and EGE (aka SAT). The math tests are hard for most of 9th- & 11th-graders. Exempli gratia, %s are learned in 6th grade, but 9th-graders usually forget 'em before the tests. The problems like "you have 10$, and x costs 3$. how many xs can you buy?" can be hard too ('cause the correct answer is 3, but 10/3(!=)3).
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