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Level 11
· ◆◆ · ~10 min
Standard Units
Standard Units
"One ruler for every scale: how many SDs above or below average is this value?"
A short lesson, then a quiz. ❤️×3 — a wrong answer costs a heart; finish with at least one left and the level is yours. Lose all three and you'll have to try again. Replay any time — XP and cleared levels are never lost.