Answers

Subtract 30/40 from 8/81

8/81 - 30/40 is -211/324.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 40 is 3240
   
   Next, find the equivalent fraction of both fractional numbers with denominator 3240
2. For the 1st fraction, since 81 × 40 = 3240,
   8/81 = 8 × 40/81 × 40 = 320/3240
3. Likewise, for the 2nd fraction, since 40 × 81 = 3240,
   30/40 = 30 × 81/40 × 81 = 2430/3240
4. Subtract the two like fractions:
   320/3240 - 2430/3240 = 320 - 2430/3240 = -2110/3240
5. After reducing the fraction, the answer is -211/324

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