Add 30/21 and 42/15
1st number: 1 9/21, 2nd number: 2 12/15
30/21 + 42/15 is 148/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
30/21 = 30 × 5/21 × 5 = 150/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
42/15 = 42 × 7/15 × 7 = 294/105 - Add the two like fractions:
150/105 + 294/105 = 150 + 294/105 = 444/105 - 444/105 simplified gives 148/35
- So, 30/21 + 42/15 = 148/35
In mixed form: 48/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/21+42/15 30/21+84/15 30/42+42/15 30/21+42/30 90/21+42/15 30/63+42/15 30/21+42/45 30/21+42/75