Subtract 72/42 from 21/75, Solve 21/75

Subtract 72/42 from 21/75

1^st number: 21/75, 2^nd number: 1 30/42

21/75 - 72/42 is -251/175.

Find the least common denominator or LCM of the two denominators:
LCM of 75 and 42 is 1050

Next, find the equivalent fraction of both fractional numbers with denominator 1050
For the 1st fraction, since 75 × 14 = 1050,
21/75 = 21 × 14/75 × 14 = 294/1050
Likewise, for the 2nd fraction, since 42 × 25 = 1050,
72/42 = 72 × 25/42 × 25 = 1800/1050
Subtract the two like fractions:
294/1050 - 1800/1050 = 294 - 1800/1050 = -1506/1050
After reducing the fraction, the answer is -251/175

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