Answers

Subtract 81/12 from 70/21

1^st number: 3 7/21, 2^nd number: 6 9/12

70/21 - 81/12 is -41/12.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 12 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 12 × 7 = 84,
   81/12 = 81 × 7/12 × 7 = 567/84
4. Subtract the two like fractions:
   280/84 - 567/84 = 280 - 567/84 = -287/84
5. After reducing the fraction, the answer is -41/12

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