Add 21/84 and 9/28
21/84 + 9/28 is 4/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
9/28 = 9 × 3/28 × 3 = 27/84 - Add the two like fractions:
21/84 + 27/84 = 21 + 27/84 = 48/84 - 48/84 simplified gives 4/7
- So, 21/84 + 9/28 = 4/7
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