Answers

Subtract 70/81 from 42/63

42/63 - 70/81 is -16/81.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 63 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 63 × 9 = 567,
   42/63 = 42 × 9/63 × 9 = 378/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   70/81 = 70 × 7/81 × 7 = 490/567
4. Subtract the two like fractions:
   378/567 - 490/567 = 378 - 490/567 = -112/567
5. After reducing the fraction, the answer is -16/81

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