Answers

Subtract 42/12 from 3/21

1^st number: 3/21, 2^nd number: 3 6/12

3/21 - 42/12 is -47/14.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 12 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   3/21 = 3 × 4/21 × 4 = 12/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   42/12 = 42 × 7/12 × 7 = 294/84
4. Subtract the two like fractions:
   12/84 - 294/84 = 12 - 294/84 = -282/84
5. After reducing the fraction, the answer is -47/14

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