TWIN
WIN

Find the Greatest Common Factor (GCF) of the numerator and denominator.
12/18 → GCF(12,18) = 6

Divide both the top and bottom by the GCF.
12÷6 = 2, 18÷6 = 3 → 2/3

Check: can you divide again? If not, you're in simplest form!

Multiply (or divide) the top and bottom by the same number.
2/3 × (4/4) = 8/12

Cross-multiply to check equivalence: if ad = bc, the fractions are equal.
2×12 = 3×8 ✓ (both = 24)

For find the missing number questions: figure out the scale factor, then multiply/divide.
3/4 = ?/12 → 4×3=12, so 3×3=9

Easy = 10 pts · hints shown · simple numbers

Medium = 20 pts · partial hints · larger numbers

Hard = 30 pts · no hints · trickiest fractions

Streak bonus: +5 per correct answer in a row (up to +30)