Answers

Subtract 3/21 from 7/42

7/42 - 3/21 is 1/42.

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,
   3/21 = 3 × 2/21 × 2 = 6/42
4. Subtract the two like fractions:
   7/42 - 6/42 = 7 - 6/42 = 1/42

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