Answers

Subtract 45/42 from 20/50

1^st number: 20/50, 2^nd number: 1 3/42

20/50 - 45/42 is -47/70.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 50 and 42 is 1050
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1050
2. For the 1st fraction, since 50 × 21 = 1050,
   20/50 = 20 × 21/50 × 21 = 420/1050
3. Likewise, for the 2nd fraction, since 42 × 25 = 1050,
   45/42 = 45 × 25/42 × 25 = 1125/1050
4. Subtract the two like fractions:
   420/1050 - 1125/1050 = 420 - 1125/1050 = -705/1050
5. After reducing the fraction, the answer is -47/70

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