Add 40/12 and 10/21
1st number: 3 4/12, 2nd number: 10/21
40/12 + 10/21 is 80/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
40/12 = 40 × 7/12 × 7 = 280/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
10/21 = 10 × 4/21 × 4 = 40/84 - Add the two like fractions:
280/84 + 40/84 = 280 + 40/84 = 320/84 - 320/84 simplified gives 80/21
- So, 40/12 + 10/21 = 80/21
In mixed form: 317/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/12+10/21 40/12+20/21 40/24+10/21 40/12+10/42 40/12+30/21 40/36+10/21 40/12+10/63 40/12+50/21 40/60+10/21 40/12+70/21 40/84+10/21