Answers

Subtract 63/81 from 81/80

1^st number: 1 1/80, 2^nd number: 63/81

81/80 - 63/81 is 169/720.

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,
   81/80 = 81 × 81/80 × 81 = 6561/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   63/81 = 63 × 80/81 × 80 = 5040/6480
4. Subtract the two like fractions:
   6561/6480 - 5040/6480 = 6561 - 5040/6480 = 1521/6480
5. After reducing the fraction, the answer is 169/720

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