Add 21/72 and 42/63
21/72 + 42/63 is 23/24.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 63 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Likewise, for the 2nd fraction, since 63 × 8 = 504,
42/63 = 42 × 8/63 × 8 = 336/504 - Add the two like fractions:
147/504 + 336/504 = 147 + 336/504 = 483/504 - 483/504 simplified gives 23/24
- So, 21/72 + 42/63 = 23/24
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/72+42/63 21/72+84/63 63/72+42/63