Add 21/12 and 42/54
1st number: 1 9/12, 2nd number: 42/54
21/12 + 42/54 is 91/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 54 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 12 × 9 = 108,
21/12 = 21 × 9/12 × 9 = 189/108 - Likewise, for the 2nd fraction, since 54 × 2 = 108,
42/54 = 42 × 2/54 × 2 = 84/108 - Add the two like fractions:
189/108 + 84/108 = 189 + 84/108 = 273/108 - 273/108 simplified gives 91/36
- So, 21/12 + 42/54 = 91/36
In mixed form: 219/36
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