Add 7/28 and 21/81
7/28 + 21/81 is 55/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 28 × 81 = 2268,
7/28 = 7 × 81/28 × 81 = 567/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
21/81 = 21 × 28/81 × 28 = 588/2268 - Add the two like fractions:
567/2268 + 588/2268 = 567 + 588/2268 = 1155/2268 - 1155/2268 simplified gives 55/108
- So, 7/28 + 21/81 = 55/108
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