Add 1/20 and 12/21
1/20 + 12/21 is 87/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
1/20 = 1 × 21/20 × 21 = 21/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
12/21 = 12 × 20/21 × 20 = 240/420 - Add the two like fractions:
21/420 + 240/420 = 21 + 240/420 = 261/420 - 261/420 simplified gives 87/140
- So, 1/20 + 12/21 = 87/140
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/20+12/21 1/20+24/21 1/40+12/21 1/20+12/42 3/20+12/21 1/20+36/21 1/60+12/21 1/20+12/63 5/20+12/21 1/20+60/21 7/20+12/21 1/20+84/21