Add 20/21 and 9/81
20/21 + 9/81 is 67/63.
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,
20/21 = 20 × 27/21 × 27 = 540/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
9/81 = 9 × 7/81 × 7 = 63/567 - Add the two like fractions:
540/567 + 63/567 = 540 + 63/567 = 603/567 - 603/567 simplified gives 67/63
- So, 20/21 + 9/81 = 67/63
In mixed form: 14/63
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