Answers

Subtract 15/42 from 8/21

8/21 - 15/42 is 1/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 42 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 21 × 2 = 42,
   8/21 = 8 × 2/21 × 2 = 16/42
3. Likewise, for the 2nd fraction, since 42 × 1 = 42,
   15/42 = 15 × 1/42 × 1 = 15/42
4. Subtract the two like fractions:
   16/42 - 15/42 = 16 - 15/42 = 1/42

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