Subtract 27/21 from 54/12, Solve 4 6/12

Subtract 27/21 from 54/12

1^st number: 4 6/12, 2^nd number: 1 6/21

54/12 - 27/21 is 45/14.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
54/12 = 54 × 7/12 × 7 = 378/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
27/21 = 27 × 4/21 × 4 = 108/84
Subtract the two like fractions:
378/84 - 108/84 = 378 - 108/84 = 270/84
After reducing the fraction, the answer is 45/14
In mixed form: 33/14

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