Add 21/54 and 20/7
1st number: 21/54, 2nd number: 2 6/7
21/54 + 20/7 is 409/126.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 7 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
21/54 = 21 × 7/54 × 7 = 147/378 - Likewise, for the 2nd fraction, since 7 × 54 = 378,
20/7 = 20 × 54/7 × 54 = 1080/378 - Add the two like fractions:
147/378 + 1080/378 = 147 + 1080/378 = 1227/378 - 1227/378 simplified gives 409/126
- So, 21/54 + 20/7 = 409/126
In mixed form: 331/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/54+20/7 21/54+40/7 21/54+20/14 63/54+20/7 21/54+60/7 21/54+20/21 21/54+20/35 21/54+20/49