Add 84/42 and 90/81
1st number: 2 0/42, 2nd number: 1 9/81
84/42 + 90/81 is 28/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
84/42 = 84 × 27/42 × 27 = 2268/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
90/81 = 90 × 14/81 × 14 = 1260/1134 - Add the two like fractions:
2268/1134 + 1260/1134 = 2268 + 1260/1134 = 3528/1134 - 3528/1134 simplified gives 28/9
- So, 84/42 + 90/81 = 28/9
In mixed form: 31/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: