Add 21/54 and 18/12
1st number: 21/54, 2nd number: 1 6/12
21/54 + 18/12 is 17/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 12 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 54 × 2 = 108,
21/54 = 21 × 2/54 × 2 = 42/108 - Likewise, for the 2nd fraction, since 12 × 9 = 108,
18/12 = 18 × 9/12 × 9 = 162/108 - Add the two like fractions:
42/108 + 162/108 = 42 + 162/108 = 204/108 - 204/108 simplified gives 17/9
- So, 21/54 + 18/12 = 17/9
In mixed form: 18/9
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