Answers

Subtract 45/40 from 20/84

1^st number: 20/84, 2^nd number: 1 5/40

20/84 - 45/40 is -149/168.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 84 × 10 = 840,
   20/84 = 20 × 10/84 × 10 = 200/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   45/40 = 45 × 21/40 × 21 = 945/840
4. Subtract the two like fractions:
   200/840 - 945/840 = 200 - 945/840 = -745/840
5. After reducing the fraction, the answer is -149/168

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