Subtract 21/45 from 20/63
20/63 - 21/45 is -47/315.
Steps for subtracting fractions
- 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,
20/63 = 20 × 5/63 × 5 = 100/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
21/45 = 21 × 7/45 × 7 = 147/315 - Subtract the two like fractions:
100/315 - 147/315 = 100 - 147/315 = -47/315
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