Add 21/42 and 1/72
21/42 + 1/72 is 37/72.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
21/42 = 21 × 12/42 × 12 = 252/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
1/72 = 1 × 7/72 × 7 = 7/504 - Add the two like fractions:
252/504 + 7/504 = 252 + 7/504 = 259/504 - 259/504 simplified gives 37/72
- So, 21/42 + 1/72 = 37/72
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/42+2/72 21/84+1/72 63/42+1/72 21/42+3/72 21/42+5/72 21/42+7/72