Add 21/30 and 70/18
1st number: 21/30, 2nd number: 3 16/18
21/30 + 70/18 is 413/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
70/18 = 70 × 5/18 × 5 = 350/90 - Add the two like fractions:
63/90 + 350/90 = 63 + 350/90 = 413/90 - So, 21/30 + 70/18 = 413/90
In mixed form: 453/90
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30+70/18 21/60+70/18 21/30+70/36 63/30+70/18 21/90+70/18 21/30+70/54 21/30+70/90