Add 21/84 and 63/81
21/84 + 63/81 is 37/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 84 × 27 = 2268,
21/84 = 21 × 27/84 × 27 = 567/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
63/81 = 63 × 28/81 × 28 = 1764/2268 - Add the two like fractions:
567/2268 + 1764/2268 = 567 + 1764/2268 = 2331/2268 - 2331/2268 simplified gives 37/36
- So, 21/84 + 63/81 = 37/36
In mixed form: 11/36
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