Answers

Subtract 7/81 from 90/80

1^st number: 1 10/80, 2^nd number: 7/81

90/80 - 7/81 is 673/648.

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,
   90/80 = 90 × 81/80 × 81 = 7290/6480
3. Likewise, for the 2nd fraction, since 81 × 80 = 6480,
   7/81 = 7 × 80/81 × 80 = 560/6480
4. Subtract the two like fractions:
   7290/6480 - 560/6480 = 7290 - 560/6480 = 6730/6480
5. After reducing the fraction, the answer is 673/648
6. In mixed form: 125/648

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