Answers

Subtract 45/7 from 12/21

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

12/21 - 45/7 is -41/7.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 7 is 21
   
   Next, find the equivalent fraction of both fractional numbers with denominator 21
2. For the 1st fraction, since 21 × 1 = 21,
   12/21 = 12 × 1/21 × 1 = 12/21
3. Likewise, for the 2nd fraction, since 7 × 3 = 21,
   45/7 = 45 × 3/7 × 3 = 135/21
4. Subtract the two like fractions:
   12/21 - 135/21 = 12 - 135/21 = -123/21
5. After reducing the fraction, the answer is -41/7

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