Answers

Subtract 40/81 from 81/90

81/90 - 40/81 is 329/810.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 90 × 9 = 810,
   81/90 = 81 × 9/90 × 9 = 729/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   40/81 = 40 × 10/81 × 10 = 400/810
4. Subtract the two like fractions:
   729/810 - 400/810 = 729 - 400/810 = 329/810

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