Answers

Subtract 40/80 from 40/90

40/90 - 40/80 is -1/18.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 80 is 720
   
   Next, find the equivalent fraction of both fractional numbers with denominator 720
2. For the 1st fraction, since 90 × 8 = 720,
   40/90 = 40 × 8/90 × 8 = 320/720
3. Likewise, for the 2nd fraction, since 80 × 9 = 720,
   40/80 = 40 × 9/80 × 9 = 360/720
4. Subtract the two like fractions:
   320/720 - 360/720 = 320 - 360/720 = -40/720
5. After reducing the fraction, the answer is -1/18

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