Answers

Subtract 16/21 from 8/42

8/42 - 16/21 is -4/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 21 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 42 × 1 = 42,
   8/42 = 8 × 1/42 × 1 = 8/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   16/21 = 16 × 2/21 × 2 = 32/42
4. Subtract the two like fractions:
   8/42 - 32/42 = 8 - 32/42 = -24/42
5. After reducing the fraction, the answer is -4/7

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