Add 21/42 and 30/81
21/42 + 30/81 is 47/54.
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,
30/81 = 30 × 14/81 × 14 = 420/1134 - Add the two like fractions:
567/1134 + 420/1134 = 567 + 420/1134 = 987/1134 - 987/1134 simplified gives 47/54
- So, 21/42 + 30/81 = 47/54
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