Answers

Subtract 81/20 from 5/42

1^st number: 5/42, 2^nd number: 4 1/20

5/42 - 81/20 is -1651/420.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 20 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 42 × 10 = 420,
   5/42 = 5 × 10/42 × 10 = 50/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   81/20 = 81 × 21/20 × 21 = 1701/420
4. Subtract the two like fractions:
   50/420 - 1701/420 = 50 - 1701/420 = -1651/420

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