Add 72/21 and 12/81
1st number: 3 9/21, 2nd number: 12/81
72/21 + 12/81 is 676/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
72/21 = 72 × 27/21 × 27 = 1944/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
12/81 = 12 × 7/81 × 7 = 84/567 - Add the two like fractions:
1944/567 + 84/567 = 1944 + 84/567 = 2028/567 - 2028/567 simplified gives 676/189
- So, 72/21 + 12/81 = 676/189
In mixed form: 3109/189
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/21+24/81 72/42+12/81 72/21+36/81 72/63+12/81 72/21+60/81 72/21+84/81