Subtract 27/56 from 72/21, Solve 3 9/21

Subtract 27/56 from 72/21

1^st number: 3 9/21, 2^nd number: 27/56

72/21 - 27/56 is 165/56.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
72/21 = 72 × 8/21 × 8 = 576/168
Likewise, for the 2nd fraction, since 56 × 3 = 168,
27/56 = 27 × 3/56 × 3 = 81/168
Subtract the two like fractions:
576/168 - 81/168 = 576 - 81/168 = 495/168
After reducing the fraction, the answer is 165/56
In mixed form: 253/56

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