Answers

Subtract 75/20 from 21/84

1^st number: 21/84, 2^nd number: 3 15/20

21/84 - 75/20 is -7/2.

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,
   21/84 = 21 × 5/84 × 5 = 105/420
3. Likewise, for the 2nd fraction, since 20 × 21 = 420,
   75/20 = 75 × 21/20 × 21 = 1575/420
4. Subtract the two like fractions:
   105/420 - 1575/420 = 105 - 1575/420 = -1470/420
5. After reducing the fraction, the answer is -7/2

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