Add 18/21 and 42/81
18/21 + 42/81 is 260/189.
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,
18/21 = 18 × 27/21 × 27 = 486/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
42/81 = 42 × 7/81 × 7 = 294/567 - Add the two like fractions:
486/567 + 294/567 = 486 + 294/567 = 780/567 - 780/567 simplified gives 260/189
- So, 18/21 + 42/81 = 260/189
In mixed form: 171/189
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