Add 21/3 and 81/12, Solve 7 0/3 + 6 9/12 as a fraction

Add 21/3 and 81/12

1^st number: 7 0/3, 2^nd number: 6 9/12

21/3 + 81/12 is 55/4.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 12 is 12

Next, find the equivalent fraction of both fractional numbers with denominator 12
For the 1st fraction, since 3 × 4 = 12,
21/3 = 21 × 4/3 × 4 = 84/12
Likewise, for the 2nd fraction, since 12 × 1 = 12,
81/12 = 81 × 1/12 × 1 = 81/12
Add the two like fractions:
84/12 + 81/12 = 84 + 81/12 = 165/12
165/12 simplified gives 55/4
So, 21/3 + 81/12 = 55/4
In mixed form: 133/4

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