Answers

Subtract 45/81 from 7/21

7/21 - 45/81 is -2/9.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   7/21 = 7 × 27/21 × 27 = 189/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   45/81 = 45 × 7/81 × 7 = 315/567
4. Subtract the two like fractions:
   189/567 - 315/567 = 189 - 315/567 = -126/567
5. After reducing the fraction, the answer is -2/9

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