Answers

Subtract 70/90 from 7/42

7/42 - 70/90 is -11/18.

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,
   7/42 = 7 × 15/42 × 15 = 105/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   70/90 = 70 × 7/90 × 7 = 490/630
4. Subtract the two like fractions:
   105/630 - 490/630 = 105 - 490/630 = -385/630
5. After reducing the fraction, the answer is -11/18

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