Answers

Subtract 80/21 from 30/84

1^st number: 30/84, 2^nd number: 3 17/21

30/84 - 80/21 is -145/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 21 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 84 × 1 = 84,
   30/84 = 30 × 1/84 × 1 = 30/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   80/21 = 80 × 4/21 × 4 = 320/84
4. Subtract the two like fractions:
   30/84 - 320/84 = 30 - 320/84 = -290/84
5. After reducing the fraction, the answer is -145/42

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