Add 12/42 and 54/81
12/42 + 54/81 is 20/21.
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,
12/42 = 12 × 27/42 × 27 = 324/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
54/81 = 54 × 14/81 × 14 = 756/1134 - Add the two like fractions:
324/1134 + 756/1134 = 324 + 756/1134 = 1080/1134 - 1080/1134 simplified gives 20/21
- So, 12/42 + 54/81 = 20/21
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