Add 28/14 and 72/21
1st number: 2 0/14, 2nd number: 3 9/21
28/14 + 72/21 is 38/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 14 × 3 = 42,
28/14 = 28 × 3/14 × 3 = 84/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
72/21 = 72 × 2/21 × 2 = 144/42 - Add the two like fractions:
84/42 + 144/42 = 84 + 144/42 = 228/42 - 228/42 simplified gives 38/7
- So, 28/14 + 72/21 = 38/7
In mixed form: 53/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/14+72/21 28/14+72/42 84/14+72/21 28/42+72/21 28/14+72/63 28/70+72/21 28/98+72/21