Add 12/21 and 9/5
1st number: 12/21, 2nd number: 1 4/5
12/21 + 9/5 is 83/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
12/21 = 12 × 5/21 × 5 = 60/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
9/5 = 9 × 21/5 × 21 = 189/105 - Add the two like fractions:
60/105 + 189/105 = 60 + 189/105 = 249/105 - 249/105 simplified gives 83/35
- So, 12/21 + 9/5 = 83/35
In mixed form: 213/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/21+9/5 12/21+18/5 12/42+9/5 12/21+9/10 36/21+9/5 12/21+27/5 12/63+9/5 12/21+9/15 60/21+9/5 12/21+45/5 12/21+9/25 84/21+9/5 12/21+63/5 12/21+9/35