Add 45/15 and 28/21
1st number: 3 0/15, 2nd number: 1 7/21
45/15 + 28/21 is 13/3.
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,
45/15 = 45 × 7/15 × 7 = 315/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Add the two like fractions:
315/105 + 140/105 = 315 + 140/105 = 455/105 - 455/105 simplified gives 13/3
- So, 45/15 + 28/21 = 13/3
In mixed form: 41/3
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/15+28/21 45/15+56/21 45/30+28/21 45/15+28/42 45/15+84/21 45/15+28/63 45/75+28/21