Answers

Subtract 90/81 from 28/45

1^st number: 28/45, 2^nd number: 1 9/81

28/45 - 90/81 is -22/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 45 and 81 is 405
   
   Next, find the equivalent fraction of both fractional numbers with denominator 405
2. For the 1st fraction, since 45 × 9 = 405,
   28/45 = 28 × 9/45 × 9 = 252/405
3. Likewise, for the 2nd fraction, since 81 × 5 = 405,
   90/81 = 90 × 5/81 × 5 = 450/405
4. Subtract the two like fractions:
   252/405 - 450/405 = 252 - 450/405 = -198/405
5. After reducing the fraction, the answer is -22/45

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