Add 18/4 and 21/81
1st number: 4 2/4, 2nd number: 21/81
18/4 + 21/81 is 257/54.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 4 × 81 = 324,
18/4 = 18 × 81/4 × 81 = 1458/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324 - Add the two like fractions:
1458/324 + 84/324 = 1458 + 84/324 = 1542/324 - 1542/324 simplified gives 257/54
- So, 18/4 + 21/81 = 257/54
In mixed form: 441/54
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/4+21/81 18/4+42/81 18/8+21/81 54/4+21/81 18/4+63/81 18/12+21/81 90/4+21/81 18/20+21/81 18/28+21/81