Add 84/27 and 75/21, Solve 3 3/27 + 3 12/21 as a fraction

Add 84/27 and 75/21

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

84/27 + 75/21 is 421/63.

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

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 27 × 7 = 189,
84/27 = 84 × 7/27 × 7 = 588/189
Likewise, for the 2nd fraction, since 21 × 9 = 189,
75/21 = 75 × 9/21 × 9 = 675/189
Add the two like fractions:
588/189 + 675/189 = 588 + 675/189 = 1263/189
1263/189 simplified gives 421/63
So, 84/27 + 75/21 = 421/63
In mixed form: 643/63

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