Add 21/81 and 9/42
21/81 + 9/42 is 179/378.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 81 × 14 = 1134,
21/81 = 21 × 14/81 × 14 = 294/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
9/42 = 9 × 27/42 × 27 = 243/1134 - Add the two like fractions:
294/1134 + 243/1134 = 294 + 243/1134 = 537/1134 - 537/1134 simplified gives 179/378
- So, 21/81 + 9/42 = 179/378
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