Add 72/42 and 21/72
1st number: 1 30/42, 2nd number: 21/72
72/42 + 21/72 is 337/168.
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,
72/42 = 72 × 12/42 × 12 = 864/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504 - Add the two like fractions:
864/504 + 147/504 = 864 + 147/504 = 1011/504 - 1011/504 simplified gives 337/168
- So, 72/42 + 21/72 = 337/168
In mixed form: 21/168
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/42+42/72 72/84+21/72 72/42+63/72