Answers

Subtract 40/21 from 20/81

1^st number: 20/81, 2^nd number: 1 19/21

20/81 - 40/21 is -940/567.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 21 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 81 × 7 = 567,
   20/81 = 20 × 7/81 × 7 = 140/567
3. Likewise, for the 2nd fraction, since 21 × 27 = 567,
   40/21 = 40 × 27/21 × 27 = 1080/567
4. Subtract the two like fractions:
   140/567 - 1080/567 = 140 - 1080/567 = -940/567

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