Subtract 21/27 from 45/12, Solve 3 9/12

Subtract 21/27 from 45/12

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

45/12 - 21/27 is 107/36.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 27 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 12 × 9 = 108,
45/12 = 45 × 9/12 × 9 = 405/108
Likewise, for the 2nd fraction, since 27 × 4 = 108,
21/27 = 21 × 4/27 × 4 = 84/108
Subtract the two like fractions:
405/108 - 84/108 = 405 - 84/108 = 321/108
After reducing the fraction, the answer is 107/36
In mixed form: 235/36

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