Answers

Subtract 70/81 from 28/42

28/42 - 70/81 is -16/81.

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,
   28/42 = 28 × 27/42 × 27 = 756/1134
3. Likewise, for the 2nd fraction, since 81 × 14 = 1134,
   70/81 = 70 × 14/81 × 14 = 980/1134
4. Subtract the two like fractions:
   756/1134 - 980/1134 = 756 - 980/1134 = -224/1134
5. After reducing the fraction, the answer is -16/81

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