Answers

Subtract 18/21 from 7/12

7/12 - 18/21 is -23/84.

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,
   7/12 = 7 × 7/12 × 7 = 49/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   18/21 = 18 × 4/21 × 4 = 72/84
4. Subtract the two like fractions:
   49/84 - 72/84 = 49 - 72/84 = -23/84

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