Subtract 20/45 from 4/63, Solve 4/63

Subtract 20/45 from 4/63

4/63 - 20/45 is -8/21.

Find the least common denominator or LCM of the two denominators:
LCM of 63 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 63 × 5 = 315,
4/63 = 4 × 5/63 × 5 = 20/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315
Subtract the two like fractions:
20/315 - 140/315 = 20 - 140/315 = -120/315
After reducing the fraction, the answer is -8/21

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