Add 63/21 and 72/45
1st number: 3 0/21, 2nd number: 1 27/45
63/21 + 72/45 is 23/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
63/21 = 63 × 15/21 × 15 = 945/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
72/45 = 72 × 7/45 × 7 = 504/315 - Add the two like fractions:
945/315 + 504/315 = 945 + 504/315 = 1449/315 - 1449/315 simplified gives 23/5
- So, 63/21 + 72/45 = 23/5
In mixed form: 43/5
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 63/42+72/45 63/21+72/90