Enter whole numbers for numerators and denominators. Denominators cannot be zero.
A fraction represents a part of a whole. It consists of a numerator (top number) and a denominator (bottom number). The numerator tells how many parts we have, and the denominator tells how many equal parts the whole is divided into.
To add fractions, find a common denominator, convert both fractions, then add the numerators:
a/b + c/d = (a*d + c*b) / (b*d) Example: 1/4 + 1/6 Common denominator: 12 = 3/12 + 2/12 = 5/12
Similar to addition, but subtract the numerators:
a/b - c/d = (a*d - c*b) / (b*d) Example: 3/4 - 1/3 = 9/12 - 4/12 = 5/12
Multiply numerators together and denominators together:
a/b * c/d = (a*c) / (b*d) Example: 2/3 * 3/4 = (2*3) / (3*4) = 6/12 = 1/2
Multiply by the reciprocal of the second fraction:
a/b / c/d = a/b * d/c = (a*d) / (b*c) Example: 2/3 / 4/5 = 2/3 * 5/4 = 10/12 = 5/6
To simplify a fraction, divide both numerator and denominator by their GCD:
12/18 = ? GCD(12, 18) = 6 12/18 = (12/6) / (18/6) = 2/3
When the numerator is larger than the denominator (improper fraction), convert to a mixed number:
17/5 = ? 17 / 5 = 3 remainder 2 17/5 = 3 2/5
Divide the numerator by the denominator:
3/4 = 3 / 4 = 0.75 1/3 = 1 / 3 = 0.333...
Recipe measurements often use fractions (1/2 cup, 3/4 teaspoon).
Measurements in inches often include fractions (3 1/2 inches).
Time signatures and note values are expressed as fractions (3/4 time, half notes).
Chances and odds are expressed as fractions.