Answers

Subtract 7/21 from 7/42

7/42 - 7/21 is -1/6.

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,
   7/42 = 7 × 1/42 × 1 = 7/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   7/21 = 7 × 2/21 × 2 = 14/42
4. Subtract the two like fractions:
   7/42 - 14/42 = 7 - 14/42 = -7/42
5. After reducing the fraction, the answer is -1/6

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