Answers

Subtract 81/21 from 56/20

1^st number: 2 16/20, 2^nd number: 3 18/21

56/20 - 81/21 is -37/35.

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,
   56/20 = 56 × 21/20 × 21 = 1176/420
3. Likewise, for the 2nd fraction, since 21 × 20 = 420,
   81/21 = 81 × 20/21 × 20 = 1620/420
4. Subtract the two like fractions:
   1176/420 - 1620/420 = 1176 - 1620/420 = -444/420
5. After reducing the fraction, the answer is -37/35

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