Answers

Subtract 30/81 from 40/90

40/90 - 30/81 is 2/27.

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,
   40/90 = 40 × 9/90 × 9 = 360/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   30/81 = 30 × 10/81 × 10 = 300/810
4. Subtract the two like fractions:
   360/810 - 300/810 = 360 - 300/810 = 60/810
5. After reducing the fraction, the answer is 2/27

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