Add 21/20 and 54/81
1st number: 1 1/20, 2nd number: 54/81
21/20 + 54/81 is 103/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
21/20 = 21 × 81/20 × 81 = 1701/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
54/81 = 54 × 20/81 × 20 = 1080/1620 - Add the two like fractions:
1701/1620 + 1080/1620 = 1701 + 1080/1620 = 2781/1620 - 2781/1620 simplified gives 103/60
- So, 21/20 + 54/81 = 103/60
In mixed form: 143/60
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/20+54/81 21/40+54/81 63/20+54/81 21/60+54/81