Add 21/63 and 9/42
21/63 + 9/42 is 23/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 63 × 2 = 126,
21/63 = 21 × 2/63 × 2 = 42/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
9/42 = 9 × 3/42 × 3 = 27/126 - Add the two like fractions:
42/126 + 27/126 = 42 + 27/126 = 69/126 - 69/126 simplified gives 23/42
- So, 21/63 + 9/42 = 23/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/63+9/42 21/63+18/42 21/63+9/84 21/63+27/42 21/63+45/42 21/63+63/42