Answers

Subtract 81/8 from 90/12

1^st number: 7 6/12, 2^nd number: 10 1/8

90/12 - 81/8 is -21/8.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 8 is 24
   
   Next, find the equivalent fraction of both fractional numbers with denominator 24
2. For the 1st fraction, since 12 × 2 = 24,
   90/12 = 90 × 2/12 × 2 = 180/24
3. Likewise, for the 2nd fraction, since 8 × 3 = 24,
   81/8 = 81 × 3/8 × 3 = 243/24
4. Subtract the two like fractions:
   180/24 - 243/24 = 180 - 243/24 = -63/24
5. After reducing the fraction, the answer is -21/8

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