Answers

Subtract 21/12 from 8/42

1^st number: 8/42, 2^nd number: 1 9/12

8/42 - 21/12 is -131/84.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 12 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   8/42 = 8 × 2/42 × 2 = 16/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   21/12 = 21 × 7/12 × 7 = 147/84
4. Subtract the two like fractions:
   16/84 - 147/84 = 16 - 147/84 = -131/84

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