Add 12/3 and 81/21
1st number: 4 0/3, 2nd number: 3 18/21
12/3 + 81/21 is 55/7.
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,
81/21 = 81 × 1/21 × 1 = 81/21 - Add the two like fractions:
84/21 + 81/21 = 84 + 81/21 = 165/21 - 165/21 simplified gives 55/7
- So, 12/3 + 81/21 = 55/7
In mixed form: 76/7
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