Answers

Subtract 10/21 from 81/20

1^st number: 4 1/20, 2^nd number: 10/21

81/20 - 10/21 is 1501/420.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 21 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 20 × 21 = 420,
   81/20 = 81 × 21/20 × 21 = 1701/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   10/21 = 10 × 20/21 × 20 = 200/420
4. Subtract the two like fractions:
   1701/420 - 200/420 = 1701 - 200/420 = 1501/420
5. In mixed form: 3241/420

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