Subtract 72/36 from 27/21, Solve 1 6/21

Subtract 72/36 from 27/21

1^st number: 1 6/21, 2^nd number: 2 0/36

27/21 - 72/36 is -5/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 21 × 12 = 252,
27/21 = 27 × 12/21 × 12 = 324/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
72/36 = 72 × 7/36 × 7 = 504/252
Subtract the two like fractions:
324/252 - 504/252 = 324 - 504/252 = -180/252
After reducing the fraction, the answer is -5/7

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