Add 90/21 and 12/9
1st number: 4 6/21, 2nd number: 1 3/9
90/21 + 12/9 is 118/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
90/21 = 90 × 3/21 × 3 = 270/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Add the two like fractions:
270/63 + 84/63 = 270 + 84/63 = 354/63 - 354/63 simplified gives 118/21
- So, 90/21 + 12/9 = 118/21
In mixed form: 513/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/21+24/9 90/42+12/9 90/21+12/18 90/21+36/9 90/63+12/9 90/21+12/27 90/21+60/9 90/21+12/45 90/21+84/9 90/21+12/63