Subtract 12/36 from 72/42, Solve 1 30/42

Subtract 12/36 from 72/42

1^st number: 1 30/42, 2^nd number: 12/36

72/42 - 12/36 is 29/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 42 × 6 = 252,
72/42 = 72 × 6/42 × 6 = 432/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
12/36 = 12 × 7/36 × 7 = 84/252
Subtract the two like fractions:
432/252 - 84/252 = 432 - 84/252 = 348/252
After reducing the fraction, the answer is 29/21
In mixed form: 18/21

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