Add 20/42 and 21/81
20/42 + 21/81 is 139/189.
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,
20/42 = 20 × 27/42 × 27 = 540/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
21/81 = 21 × 14/81 × 14 = 294/1134 - Add the two like fractions:
540/1134 + 294/1134 = 540 + 294/1134 = 834/1134 - 834/1134 simplified gives 139/189
- So, 20/42 + 21/81 = 139/189
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