Answers

Subtract 90/81 from 28/30

1^st number: 28/30, 2^nd number: 1 9/81

28/30 - 90/81 is -8/45.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 81 is 810
   
   Next, find the equivalent fraction of both fractional numbers with denominator 810
2. For the 1st fraction, since 30 × 27 = 810,
   28/30 = 28 × 27/30 × 27 = 756/810
3. Likewise, for the 2nd fraction, since 81 × 10 = 810,
   90/81 = 90 × 10/81 × 10 = 900/810
4. Subtract the two like fractions:
   756/810 - 900/810 = 756 - 900/810 = -144/810
5. After reducing the fraction, the answer is -8/45

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