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

Subtract 72/9 from 12/42

1^st number: 12/42, 2^nd number: 8 0/9

12/42 - 72/9 is -54/7.

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,
12/42 = 12 × 3/42 × 3 = 36/126
Likewise, for the 2nd fraction, since 9 × 14 = 126,
72/9 = 72 × 14/9 × 14 = 1008/126
Subtract the two like fractions:
36/126 - 1008/126 = 36 - 1008/126 = -972/126
After reducing the fraction, the answer is -54/7

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