Add 21/30 and 4/12
21/30 + 4/12 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 12 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 12 × 5 = 60,
4/12 = 4 × 5/12 × 5 = 20/60 - Add the two like fractions:
42/60 + 20/60 = 42 + 20/60 = 62/60 - 62/60 simplified gives 31/30
- So, 21/30 + 4/12 = 31/30
In mixed form: 11/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30+4/12 21/30+8/12 21/60+4/12 21/30+4/24 63/30+4/12 21/90+4/12 21/30+4/36 21/30+20/12 21/30+4/60 21/30+28/12 21/30+4/84