Answers

Subtract 40/81 from 4/80

4/80 - 40/81 is -719/1620.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 80 and 81 is 6480
   
   Next, find the equivalent fraction of both fractional numbers with denominator 6480
2. For the 1st fraction, since 80 × 81 = 6480,
   4/80 = 4 × 81/80 × 81 = 324/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   40/81 = 40 × 80/81 × 80 = 3200/6480
4. Subtract the two like fractions:
   324/6480 - 3200/6480 = 324 - 3200/6480 = -2876/6480
5. After reducing the fraction, the answer is -719/1620

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