Add 21/42 and 5/28
21/42 + 5/28 is 19/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
21/42 = 21 × 2/42 × 2 = 42/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
5/28 = 5 × 3/28 × 3 = 15/84 - Add the two like fractions:
42/84 + 15/84 = 42 + 15/84 = 57/84 - 57/84 simplified gives 19/28
- So, 21/42 + 5/28 = 19/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 21/42+10/28 21/84+5/28 21/42+5/56 63/42+5/28 21/42+15/28 21/42+5/84 21/42+25/28 21/42+35/28