Subtract 12/9 from 72/42, Solve 1 30/42

Subtract 12/9 from 72/42

1^st number: 1 30/42, 2^nd number: 1 3/9

72/42 - 12/9 is 8/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
72/42 = 72 × 3/42 × 3 = 216/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126
Subtract the two like fractions:
216/126 - 168/126 = 216 - 168/126 = 48/126
After reducing the fraction, the answer is 8/21

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