Answers

Subtract 90/5 from 81/28

1^st number: 2 25/28, 2^nd number: 18 0/5

81/28 - 90/5 is -423/28.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 28 and 5 is 140
   
   Next, find the equivalent fraction of both fractional numbers with denominator 140
2. For the 1st fraction, since 28 × 5 = 140,
   81/28 = 81 × 5/28 × 5 = 405/140
3. Likewise, for the 2nd fraction, since 5 × 28 = 140,
   90/5 = 90 × 28/5 × 28 = 2520/140
4. Subtract the two like fractions:
   405/140 - 2520/140 = 405 - 2520/140 = -2115/140
5. After reducing the fraction, the answer is -423/28

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