Answers

Subtract 21/84 from 30/42

30/42 - 21/84 is 13/28.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 84 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   30/42 = 30 × 2/42 × 2 = 60/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   21/84 = 21 × 1/84 × 1 = 21/84
4. Subtract the two like fractions:
   60/84 - 21/84 = 60 - 21/84 = 39/84
5. After reducing the fraction, the answer is 13/28

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