Subtract 70/42 from 7/72, Solve 7/72

Subtract 70/42 from 7/72

1^st number: 7/72, 2^nd number: 1 28/42

7/72 - 70/42 is -113/72.

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

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
7/72 = 7 × 7/72 × 7 = 49/504
Likewise, for the 2nd fraction, since 42 × 12 = 504,
70/42 = 70 × 12/42 × 12 = 840/504
Subtract the two like fractions:
49/504 - 840/504 = 49 - 840/504 = -791/504
After reducing the fraction, the answer is -113/72

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