Add 21/84 and 15/12
1st number: 21/84, 2nd number: 1 3/12
21/84 + 15/12 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
21/84 = 21 × 1/84 × 1 = 21/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84 - Add the two like fractions:
21/84 + 105/84 = 21 + 105/84 = 126/84 - 126/84 simplified gives 3/2
- So, 21/84 + 15/12 = 3/2
In mixed form: 11/2
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