Subtract 6/36 from 72/21, Solve 3 9/21

Subtract 6/36 from 72/21

1^st number: 3 9/21, 2^nd number: 6/36

72/21 - 6/36 is 137/42.

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,
72/21 = 72 × 12/21 × 12 = 864/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
6/36 = 6 × 7/36 × 7 = 42/252
Subtract the two like fractions:
864/252 - 42/252 = 864 - 42/252 = 822/252
After reducing the fraction, the answer is 137/42
In mixed form: 311/42

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