Add 21/4 and 15/12
1st number: 5 1/4, 2nd number: 1 3/12
21/4 + 15/12 is 13/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 12 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 4 × 3 = 12,
21/4 = 21 × 3/4 × 3 = 63/12 - Likewise, for the 2nd fraction, since 12 × 1 = 12,
15/12 = 15 × 1/12 × 1 = 15/12 - Add the two like fractions:
63/12 + 15/12 = 63 + 15/12 = 78/12 - 78/12 simplified gives 13/2
- So, 21/4 + 15/12 = 13/2
In mixed form: 61/2
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