Add 42/15 and 36/21
1st number: 2 12/15, 2nd number: 1 15/21
42/15 + 36/21 is 158/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
42/15 = 42 × 7/15 × 7 = 294/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
36/21 = 36 × 5/21 × 5 = 180/105 - Add the two like fractions:
294/105 + 180/105 = 294 + 180/105 = 474/105 - 474/105 simplified gives 158/35
- So, 42/15 + 36/21 = 158/35
In mixed form: 418/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/15+36/21 42/15+72/21 42/30+36/21 42/15+36/42 42/45+36/21 42/15+36/63 42/75+36/21