Subtract 30/72 from 54/42, Solve 1 12/42

Subtract 30/72 from 54/42

1^st number: 1 12/42, 2^nd number: 30/72

54/42 - 30/72 is 73/84.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 42 × 12 = 504,
54/42 = 54 × 12/42 × 12 = 648/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
30/72 = 30 × 7/72 × 7 = 210/504
Subtract the two like fractions:
648/504 - 210/504 = 648 - 210/504 = 438/504
After reducing the fraction, the answer is 73/84

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