Subtract 40/63 from 20/45
20/45 - 40/63 is -4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 63 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315 - Likewise, for the 2nd fraction, since 63 × 5 = 315,
40/63 = 40 × 5/63 × 5 = 200/315 - Subtract the two like fractions:
140/315 - 200/315 = 140 - 200/315 = -60/315 - After reducing the fraction, the answer is -4/21
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