Answers

Subtract 45/21 from 18/12

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

18/12 - 45/21 is -9/14.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 21 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 12 × 7 = 84,
   18/12 = 18 × 7/12 × 7 = 126/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   45/21 = 45 × 4/21 × 4 = 180/84
4. Subtract the two like fractions:
   126/84 - 180/84 = 126 - 180/84 = -54/84
5. After reducing the fraction, the answer is -9/14

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