Answers

Subtract 98/81 from 28/80

1^st number: 28/80, 2^nd number: 1 17/81

28/80 - 98/81 is -1393/1620.

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,
   28/80 = 28 × 81/80 × 81 = 2268/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   98/81 = 98 × 80/81 × 80 = 7840/6480
4. Subtract the two like fractions:
   2268/6480 - 7840/6480 = 2268 - 7840/6480 = -5572/6480
5. After reducing the fraction, the answer is -1393/1620

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