Add 21/84 and 7/56
21/84 + 7/56 is 3/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 84 × 2 = 168,
21/84 = 21 × 2/84 × 2 = 42/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
7/56 = 7 × 3/56 × 3 = 21/168 - Add the two like fractions:
42/168 + 21/168 = 42 + 21/168 = 63/168 - 63/168 simplified gives 3/8
- So, 21/84 + 7/56 = 3/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84+7/56 21/84+14/56 63/84+7/56 21/84+21/56 21/84+35/56 21/84+49/56