Add 63/81 and 5/21
63/81 + 5/21 is 64/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 21 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
63/81 = 63 × 7/81 × 7 = 441/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
5/21 = 5 × 27/21 × 27 = 135/567 - Add the two like fractions:
441/567 + 135/567 = 441 + 135/567 = 576/567 - 576/567 simplified gives 64/63
- So, 63/81 + 5/21 = 64/63
In mixed form: 11/63
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