Add 12/21 and 70/72
12/21 + 70/72 is 389/252.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
12/21 = 12 × 24/21 × 24 = 288/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
70/72 = 70 × 7/72 × 7 = 490/504 - Add the two like fractions:
288/504 + 490/504 = 288 + 490/504 = 778/504 - 778/504 simplified gives 389/252
- So, 12/21 + 70/72 = 389/252
In mixed form: 1137/252
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/21+70/72 12/42+70/72 36/21+70/72 12/63+70/72 60/21+70/72 84/21+70/72