Add 21/63 and 70/45
1st number: 21/63, 2nd number: 1 25/45
21/63 + 70/45 is 17/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
70/45 = 70 × 7/45 × 7 = 490/315 - Add the two like fractions:
105/315 + 490/315 = 105 + 490/315 = 595/315 - 595/315 simplified gives 17/9
- So, 21/63 + 70/45 = 17/9
In mixed form: 18/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/63+70/45 21/63+70/90