Answers

Subtract 25/81 from 15/80

15/80 - 25/81 is -157/1296.

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,
   15/80 = 15 × 81/80 × 81 = 1215/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   25/81 = 25 × 80/81 × 80 = 2000/6480
4. Subtract the two like fractions:
   1215/6480 - 2000/6480 = 1215 - 2000/6480 = -785/6480
5. After reducing the fraction, the answer is -157/1296

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