Add 20/21 and 12/81
20/21 + 12/81 is 208/189.
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,
12/81 = 12 × 7/81 × 7 = 84/567 - Add the two like fractions:
540/567 + 84/567 = 540 + 84/567 = 624/567 - 624/567 simplified gives 208/189
- So, 20/21 + 12/81 = 208/189
In mixed form: 119/189
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