Answers

Subtract 21/36 from 8/21

8/21 - 21/36 is -17/84.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 36 is 252
   
   Next, find the equivalent fraction of both fractional numbers with denominator 252
2. For the 1st fraction, since 21 × 12 = 252,
   8/21 = 8 × 12/21 × 12 = 96/252
3. Likewise, for the 2nd fraction, since 36 × 7 = 252,
   21/36 = 21 × 7/36 × 7 = 147/252
4. Subtract the two like fractions:
   96/252 - 147/252 = 96 - 147/252 = -51/252
5. After reducing the fraction, the answer is -17/84

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