Add 28/21 and 30/18
1st number: 1 7/21, 2nd number: 1 12/18
28/21 + 30/18 is 3/1.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
28/21 = 28 × 6/21 × 6 = 168/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126 - Add the two like fractions:
168/126 + 210/126 = 168 + 210/126 = 378/126 - 378/126 simplified gives 3/1
- So, 28/21 + 30/18 = 3/1
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/21+30/18 28/21+60/18 28/42+30/18 28/21+30/36 84/21+30/18 28/21+90/18 28/63+30/18 28/21+30/54 28/21+30/90