Add 7/21 and 63/81
7/21 + 63/81 is 10/9.
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,
63/81 = 63 × 7/81 × 7 = 441/567 - Add the two like fractions:
189/567 + 441/567 = 189 + 441/567 = 630/567 - 630/567 simplified gives 10/9
- So, 7/21 + 63/81 = 10/9
In mixed form: 11/9
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