Add 21/15 and 1/81
1st number: 1 6/15, 2nd number: 1/81
21/15 + 1/81 is 572/405.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 15 × 27 = 405,
21/15 = 21 × 27/15 × 27 = 567/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
1/81 = 1 × 5/81 × 5 = 5/405 - Add the two like fractions:
567/405 + 5/405 = 567 + 5/405 = 572/405 - So, 21/15 + 1/81 = 572/405
In mixed form: 1167/405
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/15+1/81 21/15+2/81 21/30+1/81 63/15+1/81 21/15+3/81 21/45+1/81 21/15+5/81 21/75+1/81 21/15+7/81