Answers

Subtract 81/56 from 8/21

1^st number: 8/21, 2^nd number: 1 25/56

8/21 - 81/56 is -179/168.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 56 is 168
   
   Next, find the equivalent fraction of both fractional numbers with denominator 168
2. For the 1st fraction, since 21 × 8 = 168,
   8/21 = 8 × 8/21 × 8 = 64/168
3. Likewise, for the 2nd fraction, since 56 × 3 = 168,
   81/56 = 81 × 3/56 × 3 = 243/168
4. Subtract the two like fractions:
   64/168 - 243/168 = 64 - 243/168 = -179/168

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