Add 12/21 and 4/20
12/21 + 4/20 is 27/35.
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,
12/21 = 12 × 20/21 × 20 = 240/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
4/20 = 4 × 21/20 × 21 = 84/420 - Add the two like fractions:
240/420 + 84/420 = 240 + 84/420 = 324/420 - 324/420 simplified gives 27/35
- So, 12/21 + 4/20 = 27/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/21+4/20 12/21+8/20 12/42+4/20 12/21+4/40 36/21+4/20 12/21+12/20 12/63+4/20 12/21+4/60 60/21+4/20 84/21+4/20 12/21+28/20