Add 21/12 and 15/4
1st number: 1 9/12, 2nd number: 3 3/4
21/12 + 15/4 is 11/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 4 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 4 × 3 = 12,
15/4 = 15 × 3/4 × 3 = 45/12 - Add the two like fractions:
21/12 + 45/12 = 21 + 45/12 = 66/12 - 66/12 simplified gives 11/2
- So, 21/12 + 15/4 = 11/2
In mixed form: 51/2
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