Add 21/12 and 84/18
1st number: 1 9/12, 2nd number: 4 12/18
21/12 + 84/18 is 77/12.
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,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
84/18 = 84 × 2/18 × 2 = 168/36 - Add the two like fractions:
63/36 + 168/36 = 63 + 168/36 = 231/36 - 231/36 simplified gives 77/12
- So, 21/12 + 84/18 = 77/12
In mixed form: 65/12
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