Answers

Subtract 4/12 from 20/42

20/42 - 4/12 is 1/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 12 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   20/42 = 20 × 2/42 × 2 = 40/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   4/12 = 4 × 7/12 × 7 = 28/84
4. Subtract the two like fractions:
   40/84 - 28/84 = 40 - 28/84 = 12/84
5. After reducing the fraction, the answer is 1/7

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