Add 81/27 and 20/42
1st number: 3 0/27, 2nd number: 20/42
81/27 + 20/42 is 73/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 27 × 14 = 378,
81/27 = 81 × 14/27 × 14 = 1134/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
20/42 = 20 × 9/42 × 9 = 180/378 - Add the two like fractions:
1134/378 + 180/378 = 1134 + 180/378 = 1314/378 - 1314/378 simplified gives 73/21
- So, 81/27 + 20/42 = 73/21
In mixed form: 310/21
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