Answers

Subtract 42/84 from 21/5

1^st number: 4 1/5, 2^nd number: 42/84

21/5 - 42/84 is 37/10.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 5 and 84 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 5 × 84 = 420,
   21/5 = 21 × 84/5 × 84 = 1764/420
3. Likewise, for the 2nd fraction, since 84 × 5 = 420,
   42/84 = 42 × 5/84 × 5 = 210/420
4. Subtract the two like fractions:
   1764/420 - 210/420 = 1764 - 210/420 = 1554/420
5. After reducing the fraction, the answer is 37/10
6. In mixed form: 37/10

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