Subtract 12/27 from 72/21, Solve 3 9/21

Subtract 12/27 from 72/21

1^st number: 3 9/21, 2^nd number: 12/27

72/21 - 12/27 is 188/63.

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,
12/27 = 12 × 7/27 × 7 = 84/189
Subtract the two like fractions:
648/189 - 84/189 = 648 - 84/189 = 564/189
After reducing the fraction, the answer is 188/63
In mixed form: 262/63

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