Answers

Subtract 30/84 from 12/21

12/21 - 30/84 is 3/14.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 84 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   12/21 = 12 × 4/21 × 4 = 48/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   30/84 = 30 × 1/84 × 1 = 30/84
4. Subtract the two like fractions:
   48/84 - 30/84 = 48 - 30/84 = 18/84
5. After reducing the fraction, the answer is 3/14

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