Answers

Subtract 63/80 from 28/81

28/81 - 63/80 is -2863/6480.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 80 is 6480
   
   Next, find the equivalent fraction of both fractional numbers with denominator 6480
2. For the 1st fraction, since 81 × 80 = 6480,
   28/81 = 28 × 80/81 × 80 = 2240/6480
3. Likewise, for the 2nd fraction, since 80 × 81 = 6480,
   63/80 = 63 × 81/80 × 81 = 5103/6480
4. Subtract the two like fractions:
   2240/6480 - 5103/6480 = 2240 - 5103/6480 = -2863/6480

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