Answers

Subtract 45/90 from 5/42

5/42 - 45/90 is -8/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 90 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 42 × 15 = 630,
   5/42 = 5 × 15/42 × 15 = 75/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   45/90 = 45 × 7/90 × 7 = 315/630
4. Subtract the two like fractions:
   75/630 - 315/630 = 75 - 315/630 = -240/630
5. After reducing the fraction, the answer is -8/21

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