Add 21/27 and 18/42
21/27 + 18/42 is 76/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 27 × 14 = 378,
21/27 = 21 × 14/27 × 14 = 294/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
18/42 = 18 × 9/42 × 9 = 162/378 - Add the two like fractions:
294/378 + 162/378 = 294 + 162/378 = 456/378 - 456/378 simplified gives 76/63
- So, 21/27 + 18/42 = 76/63
In mixed form: 113/63
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