Add 15/21 and 3/5
15/21 + 3/5 is 46/35.
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,
15/21 = 15 × 5/21 × 5 = 75/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
3/5 = 3 × 21/5 × 21 = 63/105 - Add the two like fractions:
75/105 + 63/105 = 75 + 63/105 = 138/105 - 138/105 simplified gives 46/35
- So, 15/21 + 3/5 = 46/35
In mixed form: 111/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21+3/5 15/21+6/5 15/42+3/5 15/21+3/10 45/21+3/5 15/21+9/5 15/63+3/5 15/21+3/15 75/21+3/5 15/21+15/5 15/21+3/25 15/21+21/5 15/21+3/35