Answers

Subtract 15/16 from 8/21

8/21 - 15/16 is -187/336.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 16 is 336
   
   Next, find the equivalent fraction of both fractional numbers with denominator 336
2. For the 1st fraction, since 21 × 16 = 336,
   8/21 = 8 × 16/21 × 16 = 128/336
3. Likewise, for the 2nd fraction, since 16 × 21 = 336,
   15/16 = 15 × 21/16 × 21 = 315/336
4. Subtract the two like fractions:
   128/336 - 315/336 = 128 - 315/336 = -187/336

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