Answers

Subtract 4/8 from 8/21

8/21 - 4/8 is -5/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 8 is 168
   
   Next, find the equivalent fraction of both fractional numbers with denominator 168
2. For the 1st fraction, since 21 × 8 = 168,
   8/21 = 8 × 8/21 × 8 = 64/168
3. Likewise, for the 2nd fraction, since 8 × 21 = 168,
   4/8 = 4 × 21/8 × 21 = 84/168
4. Subtract the two like fractions:
   64/168 - 84/168 = 64 - 84/168 = -20/168
5. After reducing the fraction, the answer is -5/42

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