Answers

Subtract 8/12 from 18/21

18/21 - 8/12 is 4/21.

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,
   18/21 = 18 × 4/21 × 4 = 72/84
3. Likewise, for the 2nd fraction, since 12 × 7 = 84,
   8/12 = 8 × 7/12 × 7 = 56/84
4. Subtract the two like fractions:
   72/84 - 56/84 = 72 - 56/84 = 16/84
5. After reducing the fraction, the answer is 4/21

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