Add 21/30 and 81/4
1st number: 21/30, 2nd number: 20 1/4
21/30 + 81/4 is 419/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 4 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Likewise, for the 2nd fraction, since 4 × 15 = 60,
81/4 = 81 × 15/4 × 15 = 1215/60 - Add the two like fractions:
42/60 + 1215/60 = 42 + 1215/60 = 1257/60 - 1257/60 simplified gives 419/20
- So, 21/30 + 81/4 = 419/20
In mixed form: 2019/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30+81/4 21/60+81/4 21/30+81/8 63/30+81/4 21/90+81/4 21/30+81/12 21/30+81/20 21/30+81/28