Answers

Subtract 20/12 from 10/42

1^st number: 10/42, 2^nd number: 1 8/12

10/42 - 20/12 is -10/7.

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,
   10/42 = 10 × 2/42 × 2 = 20/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   20/12 = 20 × 7/12 × 7 = 140/84
4. Subtract the two like fractions:
   20/84 - 140/84 = 20 - 140/84 = -120/84
5. After reducing the fraction, the answer is -10/7

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