Add 20/15 and 4/21
1st number: 1 5/15, 2nd number: 4/21
20/15 + 4/21 is 32/21.
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,
20/15 = 20 × 7/15 × 7 = 140/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
4/21 = 4 × 5/21 × 5 = 20/105 - Add the two like fractions:
140/105 + 20/105 = 140 + 20/105 = 160/105 - 160/105 simplified gives 32/21
- So, 20/15 + 4/21 = 32/21
In mixed form: 111/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/15+4/21 20/15+8/21 20/30+4/21 20/15+4/42 60/15+4/21 20/15+12/21 20/45+4/21 20/15+4/63 20/15+20/21 20/75+4/21 20/15+28/21