Answers

Subtract 40/20 from 5/42

1^st number: 5/42, 2^nd number: 2 0/20

5/42 - 40/20 is -79/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 20 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 42 × 10 = 420,
   5/42 = 5 × 10/42 × 10 = 50/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   40/20 = 40 × 21/20 × 21 = 840/420
4. Subtract the two like fractions:
   50/420 - 840/420 = 50 - 840/420 = -790/420
5. After reducing the fraction, the answer is -79/42

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