Add 70/81 and 21/63
70/81 + 21/63 is 97/81.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 63 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
70/81 = 70 × 7/81 × 7 = 490/567 - Likewise, for the 2nd fraction, since 63 × 9 = 567,
21/63 = 21 × 9/63 × 9 = 189/567 - Add the two like fractions:
490/567 + 189/567 = 490 + 189/567 = 679/567 - 679/567 simplified gives 97/81
- So, 70/81 + 21/63 = 97/81
In mixed form: 116/81
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 70/81+42/63