Answers

Subtract 45/56 from 20/40

20/40 - 45/56 is -17/56.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 56 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 40 × 7 = 280,
   20/40 = 20 × 7/40 × 7 = 140/280
3. Likewise, for the 2nd fraction, since 56 × 5 = 280,
   45/56 = 45 × 5/56 × 5 = 225/280
4. Subtract the two like fractions:
   140/280 - 225/280 = 140 - 225/280 = -85/280
5. After reducing the fraction, the answer is -17/56

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