Answers

Subtract 35/20 from 42/84

1^st number: 42/84, 2^nd number: 1 15/20

42/84 - 35/20 is -5/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 20 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 84 × 5 = 420,
   42/84 = 42 × 5/84 × 5 = 210/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   35/20 = 35 × 21/20 × 21 = 735/420
4. Subtract the two like fractions:
   210/420 - 735/420 = 210 - 735/420 = -525/420
5. After reducing the fraction, the answer is -5/4

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