Add 27/54 and 12/21
27/54 + 12/21 is 15/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
27/54 = 27 × 7/54 × 7 = 189/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
12/21 = 12 × 18/21 × 18 = 216/378 - Add the two like fractions:
189/378 + 216/378 = 189 + 216/378 = 405/378 - 405/378 simplified gives 15/14
- So, 27/54 + 12/21 = 15/14
In mixed form: 11/14
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