Subtract 21/72 from 15/63, Solve 15/63

Subtract 21/72 from 15/63

15/63 - 21/72 is -3/56.

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

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 63 × 8 = 504,
15/63 = 15 × 8/63 × 8 = 120/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
21/72 = 21 × 7/72 × 7 = 147/504
Subtract the two like fractions:
120/504 - 147/504 = 120 - 147/504 = -27/504
After reducing the fraction, the answer is -3/56

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