Answers

Subtract 63/20 from 21/64

1^st number: 21/64, 2^nd number: 3 3/20

21/64 - 63/20 is -903/320.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 64 and 20 is 320
   
   Next, find the equivalent fraction of both fractional numbers with denominator 320
2. For the 1st fraction, since 64 × 5 = 320,
   21/64 = 21 × 5/64 × 5 = 105/320
3. Likewise, for the 2nd fraction, since 20 × 16 = 320,
   63/20 = 63 × 16/20 × 16 = 1008/320
4. Subtract the two like fractions:
   105/320 - 1008/320 = 105 - 1008/320 = -903/320

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