Add 21/12 and 18/3
1st number: 1 9/12, 2nd number: 6 0/3
21/12 + 18/3 is 31/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 3 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 12 × 1 = 12,
21/12 = 21 × 1/12 × 1 = 21/12 - Likewise, for the 2nd fraction, since 3 × 4 = 12,
18/3 = 18 × 4/3 × 4 = 72/12 - Add the two like fractions:
21/12 + 72/12 = 21 + 72/12 = 93/12 - 93/12 simplified gives 31/4
- So, 21/12 + 18/3 = 31/4
In mixed form: 73/4
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