Answers

Subtract 20/42 from 45/40

1^st number: 1 5/40, 2^nd number: 20/42

45/40 - 20/42 is 109/168.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 42 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 40 × 21 = 840,
   45/40 = 45 × 21/40 × 21 = 945/840
3. Likewise, for the 2nd fraction, since 42 × 20 = 840,
   20/42 = 20 × 20/42 × 20 = 400/840
4. Subtract the two like fractions:
   945/840 - 400/840 = 945 - 400/840 = 545/840
5. After reducing the fraction, the answer is 109/168

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