Add 90/7 and 21/18
1st number: 12 6/7, 2nd number: 1 3/18
90/7 + 21/18 is 589/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 7 × 18 = 126,
90/7 = 90 × 18/7 × 18 = 1620/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
21/18 = 21 × 7/18 × 7 = 147/126 - Add the two like fractions:
1620/126 + 147/126 = 1620 + 147/126 = 1767/126 - 1767/126 simplified gives 589/42
- So, 90/7 + 21/18 = 589/42
In mixed form: 141/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/7+42/18 90/14+21/18 90/7+21/36 90/7+63/18 90/21+21/18 90/7+21/54 90/35+21/18 90/7+21/90 90/49+21/18