Answers

Subtract 81/42 from 63/84

1^st number: 63/84, 2^nd number: 1 39/42

63/84 - 81/42 is -33/28.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 42 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 84 × 1 = 84,
   63/84 = 63 × 1/84 × 1 = 63/84
3. Likewise, for the 2nd fraction, since 42 × 2 = 84,
   81/42 = 81 × 2/42 × 2 = 162/84
4. Subtract the two like fractions:
   63/84 - 162/84 = 63 - 162/84 = -99/84
5. After reducing the fraction, the answer is -33/28

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