Subtract 72/63 from 1/42, Solve 1/42

Subtract 72/63 from 1/42

1^st number: 1/42, 2^nd number: 1 9/63

1/42 - 72/63 is -47/42.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 42 × 3 = 126,
1/42 = 1 × 3/42 × 3 = 3/126
Likewise, for the 2nd fraction, since 63 × 2 = 126,
72/63 = 72 × 2/63 × 2 = 144/126
Subtract the two like fractions:
3/126 - 144/126 = 3 - 144/126 = -141/126
After reducing the fraction, the answer is -47/42

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