Add 21/70 and 42/20
1st number: 21/70, 2nd number: 2 2/20
21/70 + 42/20 is 12/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 70 × 2 = 140,
21/70 = 21 × 2/70 × 2 = 42/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
42/20 = 42 × 7/20 × 7 = 294/140 - Add the two like fractions:
42/140 + 294/140 = 42 + 294/140 = 336/140 - 336/140 simplified gives 12/5
- So, 21/70 + 42/20 = 12/5
In mixed form: 22/5
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/70+42/20 21/70+84/20 21/70+42/40 63/70+42/20 21/70+42/60