Add 7/21 and 30/54
7/21 + 30/54 is 8/9.
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,
7/21 = 7 × 18/21 × 18 = 126/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
30/54 = 30 × 7/54 × 7 = 210/378 - Add the two like fractions:
126/378 + 210/378 = 126 + 210/378 = 336/378 - 336/378 simplified gives 8/9
- So, 7/21 + 30/54 = 8/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/21+30/54 7/21+60/54 7/42+30/54 7/21+90/54 7/63+30/54 35/21+30/54 49/21+30/54