Add 54/15 and 21/81
1st number: 3 9/15, 2nd number: 21/81
54/15 + 21/81 is 521/135.
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,
54/15 = 54 × 27/15 × 27 = 1458/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
21/81 = 21 × 5/81 × 5 = 105/405 - Add the two like fractions:
1458/405 + 105/405 = 1458 + 105/405 = 1563/405 - 1563/405 simplified gives 521/135
- So, 54/15 + 21/81 = 521/135
In mixed form: 3116/135
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/15+42/81 54/30+21/81 54/15+63/81 54/45+21/81 54/75+21/81