Add 20/81 and 40/42
20/81 + 40/42 is 680/567.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 81 × 14 = 1134,
20/81 = 20 × 14/81 × 14 = 280/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
40/42 = 40 × 27/42 × 27 = 1080/1134 - Add the two like fractions:
280/1134 + 1080/1134 = 280 + 1080/1134 = 1360/1134 - 1360/1134 simplified gives 680/567
- So, 20/81 + 40/42 = 680/567
In mixed form: 1113/567
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