Add 21/45 and 63/42
1st number: 21/45, 2nd number: 1 21/42
21/45 + 63/42 is 59/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
21/45 = 21 × 14/45 × 14 = 294/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
63/42 = 63 × 15/42 × 15 = 945/630 - Add the two like fractions:
294/630 + 945/630 = 294 + 945/630 = 1239/630 - 1239/630 simplified gives 59/30
- So, 21/45 + 63/42 = 59/30
In mixed form: 129/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/45+63/42 21/90+63/42 21/45+63/84 63/45+63/42