Answers

Subtract 84/81 from 7/42

1^st number: 7/42, 2^nd number: 1 3/81

7/42 - 84/81 is -47/54.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 81 is 1134
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1134
2. For the 1st fraction, since 42 × 27 = 1134,
   7/42 = 7 × 27/42 × 27 = 189/1134
3. Likewise, for the 2nd fraction, since 81 × 14 = 1134,
   84/81 = 84 × 14/81 × 14 = 1176/1134
4. Subtract the two like fractions:
   189/1134 - 1176/1134 = 189 - 1176/1134 = -987/1134
5. After reducing the fraction, the answer is -47/54

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