Add 18/15 and 5/21
1st number: 1 3/15, 2nd number: 5/21
18/15 + 5/21 is 151/105.
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,
18/15 = 18 × 7/15 × 7 = 126/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
5/21 = 5 × 5/21 × 5 = 25/105 - Add the two like fractions:
126/105 + 25/105 = 126 + 25/105 = 151/105 - So, 18/15 + 5/21 = 151/105
In mixed form: 146/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/15+5/21 18/15+10/21 18/30+5/21 18/15+5/42 54/15+5/21 18/15+15/21 18/45+5/21 18/15+5/63 90/15+5/21 18/15+25/21 18/75+5/21 18/15+35/21