Add 7/42 and 21/81
7/42 + 21/81 is 23/54.
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,
7/42 = 7 × 27/42 × 27 = 189/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
21/81 = 21 × 14/81 × 14 = 294/1134 - Add the two like fractions:
189/1134 + 294/1134 = 189 + 294/1134 = 483/1134 - 483/1134 simplified gives 23/54
- So, 7/42 + 21/81 = 23/54
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