Add 1/18 and 72/21
1st number: 1/18, 2nd number: 3 9/21
1/18 + 72/21 is 439/126.
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,
1/18 = 1 × 7/18 × 7 = 7/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
72/21 = 72 × 6/21 × 6 = 432/126 - Add the two like fractions:
7/126 + 432/126 = 7 + 432/126 = 439/126 - So, 1/18 + 72/21 = 439/126
In mixed form: 361/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/18+72/21 1/36+72/21 1/18+72/42 3/18+72/21 1/54+72/21 1/18+72/63 5/18+72/21 1/90+72/21 7/18+72/21