Add 21/84 and 4/81
21/84 + 4/81 is 97/324.
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,
4/81 = 4 × 28/81 × 28 = 112/2268 - Add the two like fractions:
567/2268 + 112/2268 = 567 + 112/2268 = 679/2268 - 679/2268 simplified gives 97/324
- So, 21/84 + 4/81 = 97/324
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