Add 21/18 and 3/12
1st number: 1 3/18, 2nd number: 3/12
21/18 + 3/12 is 17/12.
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,
21/18 = 21 × 2/18 × 2 = 42/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
3/12 = 3 × 3/12 × 3 = 9/36 - Add the two like fractions:
42/36 + 9/36 = 42 + 9/36 = 51/36 - 51/36 simplified gives 17/12
- So, 21/18 + 3/12 = 17/12
In mixed form: 15/12
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