Add 21/42 and 42/81
21/42 + 42/81 is 55/54.
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,
21/42 = 21 × 27/42 × 27 = 567/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
42/81 = 42 × 14/81 × 14 = 588/1134 - Add the two like fractions:
567/1134 + 588/1134 = 567 + 588/1134 = 1155/1134 - 1155/1134 simplified gives 55/54
- So, 21/42 + 42/81 = 55/54
In mixed form: 11/54
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