Answers

Subtract 45/5 from 81/20

1^st number: 4 1/20, 2^nd number: 9 0/5

81/20 - 45/5 is -99/20.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 5 is 20
   
   Next, find the equivalent fraction of both fractional numbers with denominator 20
2. For the 1st fraction, since 20 × 1 = 20,
   81/20 = 81 × 1/20 × 1 = 81/20
3. Likewise, for the 2nd fraction, since 5 × 4 = 20,
   45/5 = 45 × 4/5 × 4 = 180/20
4. Subtract the two like fractions:
   81/20 - 180/20 = 81 - 180/20 = -99/20

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