Add 15/45 and 21/20
1st number: 15/45, 2nd number: 1 1/20
15/45 + 21/20 is 83/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
15/45 = 15 × 4/45 × 4 = 60/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Add the two like fractions:
60/180 + 189/180 = 60 + 189/180 = 249/180 - 249/180 simplified gives 83/60
- So, 15/45 + 21/20 = 83/60
In mixed form: 123/60
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/45+21/20 15/45+42/20 15/90+21/20 15/45+21/40 15/45+63/20 15/45+21/60 75/45+21/20