Answers

Subtract 40/42 from 27/63

27/63 - 40/42 is -11/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 63 and 42 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 63 × 2 = 126,
   27/63 = 27 × 2/63 × 2 = 54/126
3. Likewise, for the 2nd fraction, since 42 × 3 = 126,
   40/42 = 40 × 3/42 × 3 = 120/126
4. Subtract the two like fractions:
   54/126 - 120/126 = 54 - 120/126 = -66/126
5. After reducing the fraction, the answer is -11/21

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