Answers

Subtract 12/9 from 21/18

1^st number: 1 3/18, 2^nd number: 1 3/9

21/18 - 12/9 is -1/6.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 9 is 18
   
   Next, find the equivalent fraction of both fractional numbers with denominator 18
2. For the 1st fraction, since 18 × 1 = 18,
   21/18 = 21 × 1/18 × 1 = 21/18
3. Likewise, for the 2nd fraction, since 9 × 2 = 18,
   12/9 = 12 × 2/9 × 2 = 24/18
4. Subtract the two like fractions:
   21/18 - 24/18 = 21 - 24/18 = -3/18
5. After reducing the fraction, the answer is -1/6

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