Subtract 70/63 from 12/72, Solve 12/72

Subtract 70/63 from 12/72

1^st number: 12/72, 2^nd number: 1 7/63

12/72 - 70/63 is -17/18.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 63 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
12/72 = 12 × 7/72 × 7 = 84/504
Likewise, for the 2nd fraction, since 63 × 8 = 504,
70/63 = 70 × 8/63 × 8 = 560/504
Subtract the two like fractions:
84/504 - 560/504 = 84 - 560/504 = -476/504
After reducing the fraction, the answer is -17/18

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