Add 72/21 and 30/27, Solve 3 9/21 + 1 3/27 as a fraction

Add 72/21 and 30/27

1^st number: 3 9/21, 2^nd number: 1 3/27

72/21 + 30/27 is 286/63.

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,
72/21 = 72 × 9/21 × 9 = 648/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
30/27 = 30 × 7/27 × 7 = 210/189
Add the two like fractions:
648/189 + 210/189 = 648 + 210/189 = 858/189
858/189 simplified gives 286/63
So, 72/21 + 30/27 = 286/63
In mixed form: 434/63

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