Answers

Subtract 9/21 from 8/12

8/12 - 9/21 is 5/21.

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,
   8/12 = 8 × 7/12 × 7 = 56/84
3. Likewise, for the 2nd fraction, since 21 × 4 = 84,
   9/21 = 9 × 4/21 × 4 = 36/84
4. Subtract the two like fractions:
   56/84 - 36/84 = 56 - 36/84 = 20/84
5. After reducing the fraction, the answer is 5/21

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