Answers

Subtract 21/10 from 20/81

1^st number: 20/81, 2^nd number: 2 1/10

20/81 - 21/10 is -1501/810.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 10 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 81 × 10 = 810,
   20/81 = 20 × 10/81 × 10 = 200/810
3. Likewise, for the 2nd fraction, since 10 × 81 = 810,
   21/10 = 21 × 81/10 × 81 = 1701/810
4. Subtract the two like fractions:
   200/810 - 1701/810 = 200 - 1701/810 = -1501/810

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