Add 27/18 and 21/12
1st number: 1 9/18, 2nd number: 1 9/12
27/18 + 21/12 is 13/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 18 × 2 = 36,
27/18 = 27 × 2/18 × 2 = 54/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
21/12 = 21 × 3/12 × 3 = 63/36 - Add the two like fractions:
54/36 + 63/36 = 54 + 63/36 = 117/36 - 117/36 simplified gives 13/4
- So, 27/18 + 21/12 = 13/4
In mixed form: 31/4
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