Answers

Subtract 21/64 from 21/40

21/40 - 21/64 is 63/320.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 64 is 320
   
   Next, find the equivalent fraction of both fractional numbers with denominator 320
2. For the 1st fraction, since 40 × 8 = 320,
   21/40 = 21 × 8/40 × 8 = 168/320
3. Likewise, for the 2nd fraction, since 64 × 5 = 320,
   21/64 = 21 × 5/64 × 5 = 105/320
4. Subtract the two like fractions:
   168/320 - 105/320 = 168 - 105/320 = 63/320

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