Add 21/27 and 12/18
21/27 + 12/18 is 13/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 18 is 54
Next, find the equivalent fraction of both fractional numbers with denominator 54 - For the 1st fraction, since 27 × 2 = 54,
21/27 = 21 × 2/27 × 2 = 42/54 - Likewise, for the 2nd fraction, since 18 × 3 = 54,
12/18 = 12 × 3/18 × 3 = 36/54 - Add the two like fractions:
42/54 + 36/54 = 42 + 36/54 = 78/54 - 78/54 simplified gives 13/9
- So, 21/27 + 12/18 = 13/9
In mixed form: 14/9
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