Answers

Subtract 80/84 from 70/21

1^st number: 3 7/21, 2^nd number: 80/84

70/21 - 80/84 is 50/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 84 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   70/21 = 70 × 4/21 × 4 = 280/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   80/84 = 80 × 1/84 × 1 = 80/84
4. Subtract the two like fractions:
   280/84 - 80/84 = 280 - 80/84 = 200/84
5. After reducing the fraction, the answer is 50/21
6. In mixed form: 28/21

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