Add 63/21 and 12/27, Solve 3 0/21 + 12/27 as a fraction

Add 63/21 and 12/27

1^st number: 3 0/21, 2^nd number: 12/27

63/21 + 12/27 is 31/9.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
63/21 = 63 × 9/21 × 9 = 567/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
12/27 = 12 × 7/27 × 7 = 84/189
Add the two like fractions:
567/189 + 84/189 = 567 + 84/189 = 651/189
651/189 simplified gives 31/9
So, 63/21 + 12/27 = 31/9
In mixed form: 34/9

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