Add 5/81 and 21/20
1st number: 5/81, 2nd number: 1 1/20
5/81 + 21/20 is 1801/1620.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 20 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 81 × 20 = 1620,
5/81 = 5 × 20/81 × 20 = 100/1620 - Likewise, for the 2nd fraction, since 20 × 81 = 1620,
21/20 = 21 × 81/20 × 81 = 1701/1620 - Add the two like fractions:
100/1620 + 1701/1620 = 100 + 1701/1620 = 1801/1620 - So, 5/81 + 21/20 = 1801/1620
In mixed form: 1181/1620
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/81+21/20 5/81+42/20 5/81+21/40 15/81+21/20 5/81+63/20 5/81+21/60 25/81+21/20 35/81+21/20