Add 40/21 and 30/18
1st number: 1 19/21, 2nd number: 1 12/18
40/21 + 30/18 is 25/7.
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,
40/21 = 40 × 6/21 × 6 = 240/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
30/18 = 30 × 7/18 × 7 = 210/126 - Add the two like fractions:
240/126 + 210/126 = 240 + 210/126 = 450/126 - 450/126 simplified gives 25/7
- So, 40/21 + 30/18 = 25/7
In mixed form: 34/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/21+30/18 40/21+60/18 40/42+30/18 40/21+30/36 40/21+90/18 40/63+30/18 40/21+30/54 40/21+30/90