Add 18/42 and 21/81
18/42 + 21/81 is 130/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
18/42 = 18 × 27/42 × 27 = 486/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
21/81 = 21 × 14/81 × 14 = 294/1134 - Add the two like fractions:
486/1134 + 294/1134 = 486 + 294/1134 = 780/1134 - 780/1134 simplified gives 130/189
- So, 18/42 + 21/81 = 130/189
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