Answers

Subtract 21/30 from 12/81

12/81 - 21/30 is -149/270.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 30 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 81 × 10 = 810,
   12/81 = 12 × 10/81 × 10 = 120/810
3. Likewise, for the 2nd fraction, since 30 × 27 = 810,
   21/30 = 21 × 27/30 × 27 = 567/810
4. Subtract the two like fractions:
   120/810 - 567/810 = 120 - 567/810 = -447/810
5. After reducing the fraction, the answer is -149/270

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