Add 8/18 and 42/21
1st number: 8/18, 2nd number: 2 0/21
8/18 + 42/21 is 22/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
42/21 = 42 × 6/21 × 6 = 252/126 - Add the two like fractions:
56/126 + 252/126 = 56 + 252/126 = 308/126 - 308/126 simplified gives 22/9
- So, 8/18 + 42/21 = 22/9
In mixed form: 24/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/18+42/21 8/18+84/21 8/36+42/21 24/18+42/21 8/54+42/21 8/18+42/63 40/18+42/21 8/90+42/21 56/18+42/21