Add 7/21 and 4/81
7/21 + 4/81 is 31/81.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
7/21 = 7 × 27/21 × 27 = 189/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
4/81 = 4 × 7/81 × 7 = 28/567 - Add the two like fractions:
189/567 + 28/567 = 189 + 28/567 = 217/567 - 217/567 simplified gives 31/81
- So, 7/21 + 4/81 = 31/81
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