Add 42/21 and 7/20
1st number: 2 0/21, 2nd number: 7/20
42/21 + 7/20 is 47/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420 - Add the two like fractions:
840/420 + 147/420 = 840 + 147/420 = 987/420 - 987/420 simplified gives 47/20
- So, 42/21 + 7/20 = 47/20
In mixed form: 27/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/21+7/20 42/21+14/20 42/21+7/40 42/21+21/20 42/63+7/20 42/21+7/60 42/21+35/20 42/21+49/20