Add 81/84 and 21/27
81/84 + 21/27 is 439/252.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 27 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 84 × 9 = 756,
81/84 = 81 × 9/84 × 9 = 729/756 - Likewise, for the 2nd fraction, since 27 × 28 = 756,
21/27 = 21 × 28/27 × 28 = 588/756 - Add the two like fractions:
729/756 + 588/756 = 729 + 588/756 = 1317/756 - 1317/756 simplified gives 439/252
- So, 81/84 + 21/27 = 439/252
In mixed form: 1187/252
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