Fractions trip people up because each operation follows a different rule: addition needs common denominators, multiplication doesn't, and division flips things upside down. This calculator performs all four operations and always returns the answer fully simplified.
Cómo funciona
Enter two fractions and pick the operation. The calculator applies the correct rule, then divides numerator and denominator by their greatest common factor to give the simplest form, alongside the decimal value.
La fórmula
Subtraction mirrors addition with a minus sign. Division works by multiplying by the reciprocal of the second fraction — the classic 'keep, change, flip'.
Ejemplo resuelto
1/2 + 1/3: cross-multiply to get (1×3 + 1×2) ÷ (2×3) = 5/6 ≈ 0.8333. Already in simplest form, since 5 and 6 share no common factor.
Preguntas frecuentes
Why can't I just add numerators and denominators?
Because fractions are ratios, not pairs of counts. 1/2 + 1/3 is not 2/5 (= 0.4) — that's smaller than 1/2 alone. Common denominators express both parts in the same-sized pieces first.
How do I work with mixed numbers like 2½?
Convert to an improper fraction first: 2½ = 5/2. Do the arithmetic, then convert back if needed — 5/2 × 1/3 = 5/6.
Why does dividing by a fraction make numbers bigger?
Dividing by ½ asks 'how many halves fit inside?' — twice as many as wholes. Dividing by any number below 1 must therefore give a larger result.