Add 20/21 and 12/54
20/21 + 12/54 is 74/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 21 × 18 = 378,
20/21 = 20 × 18/21 × 18 = 360/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
12/54 = 12 × 7/54 × 7 = 84/378 - Add the two like fractions:
360/378 + 84/378 = 360 + 84/378 = 444/378 - 444/378 simplified gives 74/63
- So, 20/21 + 12/54 = 74/63
In mixed form: 111/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21+12/54 20/21+24/54 20/42+12/54 60/21+12/54 20/21+36/54 20/63+12/54 20/21+60/54 20/21+84/54