Answers

Subtract 20/40 from 30/42

30/42 - 20/40 is 3/14.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 40 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 42 × 20 = 840,
   30/42 = 30 × 20/42 × 20 = 600/840
3. Likewise, for the 2nd fraction, since 40 × 21 = 840,
   20/40 = 20 × 21/40 × 21 = 420/840
4. Subtract the two like fractions:
   600/840 - 420/840 = 600 - 420/840 = 180/840
5. After reducing the fraction, the answer is 3/14

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