Answers

Subtract 90/5 from 81/12

1^st number: 6 9/12, 2^nd number: 18 0/5

81/12 - 90/5 is -45/4.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 5 is 60
   
   Next, find the equivalent fraction of both fractional numbers with denominator 60
2. For the 1st fraction, since 12 × 5 = 60,
   81/12 = 81 × 5/12 × 5 = 405/60
3. Likewise, for the 2nd fraction, since 5 × 12 = 60,
   90/5 = 90 × 12/5 × 12 = 1080/60
4. Subtract the two like fractions:
   405/60 - 1080/60 = 405 - 1080/60 = -675/60
5. After reducing the fraction, the answer is -45/4

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