Find what is actually being asked

Read the last sentence of the problem before the rest of it. Contest problems routinely give you a natural quantity to find and then ask for something one step further - twice it, the number left over, the other one of the pair. Underlining the actual question costs five seconds.

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Work through it

LearnWhat it is, how to spot it, a worked example, and where it goes wrong.
Practice — 3-point ladder2 problems. Three in a row finishes it.0/3 in a row · 0/2 solved
Practice — 4-point ladder2 problems. Three in a row finishes it.0/3 in a row · 0/2 solved
Practice — 5-point ladderNo problems written at this tier yet.Nothing written at this tier yet
Skill quizFinish every ladder that has problems first.Finish the ladders above first

Before and after

Needs first

Nothing. This is one of the skills the Atlas starts from.

Opens up

CFT-03Try small cases first CFT-04Back-solve from the answer choices CFT-05Eliminate impossible choices by bounding CFT-10Check units and re-read before bubbling

In official papers

No indexed official paper question has been tagged with CFT-01 yet. The index grows one paper at a time, and it records only question numbers, point values and our own skill tags — never the problems themselves.

See the papers indexed so far

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