Add 21/28 and 9/84
21/28 + 9/84 is 6/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
21/28 = 21 × 3/28 × 3 = 63/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
9/84 = 9 × 1/84 × 1 = 9/84 - Add the two like fractions:
63/84 + 9/84 = 63 + 9/84 = 72/84 - 72/84 simplified gives 6/7
- So, 21/28 + 9/84 = 6/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/28+9/84 21/28+18/84 21/56+9/84 63/28+9/84 21/28+27/84 21/84+9/84 21/28+45/84 21/28+63/84