Add 20/81 and 12/80
20/81 + 12/80 is 643/1620.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 80 is 6480
Next, find the equivalent fraction of both fractional numbers with denominator 6480 - For the 1st fraction, since 81 × 80 = 6480,
20/81 = 20 × 80/81 × 80 = 1600/6480 - Likewise, for the 2nd fraction, since 80 × 81 = 6480,
12/80 = 12 × 81/80 × 81 = 972/6480 - Add the two like fractions:
1600/6480 + 972/6480 = 1600 + 972/6480 = 2572/6480 - 2572/6480 simplified gives 643/1620
- So, 20/81 + 12/80 = 643/1620
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/81+12/80 20/81+24/80 60/81+12/80 20/81+36/80 20/81+60/80 20/81+84/80