Answers

Subtract 20/70 from 8/42

8/42 - 20/70 is -2/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 70 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 42 × 5 = 210,
   8/42 = 8 × 5/42 × 5 = 40/210
3. Likewise, for the 2nd fraction, since 70 × 3 = 210,
   20/70 = 20 × 3/70 × 3 = 60/210
4. Subtract the two like fractions:
   40/210 - 60/210 = 40 - 60/210 = -20/210
5. After reducing the fraction, the answer is -2/21

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