Add 21/63 and 12/27
21/63 + 12/27 is 7/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 63 × 3 = 189,
21/63 = 21 × 3/63 × 3 = 63/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
12/27 = 12 × 7/27 × 7 = 84/189 - Add the two like fractions:
63/189 + 84/189 = 63 + 84/189 = 147/189 - 147/189 simplified gives 7/9
- So, 21/63 + 12/27 = 7/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/63+12/27 21/63+24/27 21/63+12/54 21/63+36/27 21/63+12/81 21/63+60/27 21/63+84/27