Add 15/12 and 21/18
1st number: 1 3/12, 2nd number: 1 3/18
15/12 + 21/18 is 29/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
15/12 = 15 × 3/12 × 3 = 45/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36 - Add the two like fractions:
45/36 + 42/36 = 45 + 42/36 = 87/36 - 87/36 simplified gives 29/12
- So, 15/12 + 21/18 = 29/12
In mixed form: 25/12
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