Add 12/3 and 15/21
1st number: 4 0/3, 2nd number: 15/21
12/3 + 15/21 is 33/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
12/3 = 12 × 7/3 × 7 = 84/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
15/21 = 15 × 1/21 × 1 = 15/21 - Add the two like fractions:
84/21 + 15/21 = 84 + 15/21 = 99/21 - 99/21 simplified gives 33/7
- So, 12/3 + 15/21 = 33/7
In mixed form: 45/7
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