Add 21/3 and 18/12
1st number: 7 0/3, 2nd number: 1 6/12
21/3 + 18/12 is 17/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 12 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 3 × 4 = 12,
21/3 = 21 × 4/3 × 4 = 84/12 - Likewise, for the 2nd fraction, since 12 × 1 = 12,
18/12 = 18 × 1/12 × 1 = 18/12 - Add the two like fractions:
84/12 + 18/12 = 84 + 18/12 = 102/12 - 102/12 simplified gives 17/2
- So, 21/3 + 18/12 = 17/2
In mixed form: 81/2
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