Answers

Subtract 81/64 from 1/21

1^st number: 1/21, 2^nd number: 1 17/64

1/21 - 81/64 is -1637/1344.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 64 is 1344
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1344
2. For the 1st fraction, since 21 × 64 = 1344,
   1/21 = 1 × 64/21 × 64 = 64/1344
3. Likewise, for the 2nd fraction, since 64 × 21 = 1344,
   81/64 = 81 × 21/64 × 21 = 1701/1344
4. Subtract the two like fractions:
   64/1344 - 1701/1344 = 64 - 1701/1344 = -1637/1344

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