Back-solve from the answer choices

The answer is one of the five given. Testing a choice is often much easier than solving forwards, especially when the forward route needs algebra. Start with the middle choice so that the result tells you which direction to move.

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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 ladderNo problems written at this tier yet.Nothing written at this tier yet
Practice — 4-point ladder2 problems. Three in a row finishes it.0/3 in a row · 0/2 solved
Practice — 5-point ladder1 problem. Three in a row finishes it.0/3 in a row · 0/1 solved
Skill quizFinish every ladder that has problems first.Finish the ladders above first

Before and after

Needs first

CFT-01Find what is actually being asked

Opens up

CFT-11Sanity-check with a second method

In official papers

No indexed official paper question has been tagged with CFT-04 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.

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