Answers

Subtract 81/8 from 90/40

1^st number: 2 10/40, 2^nd number: 10 1/8

90/40 - 81/8 is -63/8.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 8 is 40
   
   Next, find the equivalent fraction of both fractional numbers with denominator 40
2. For the 1st fraction, since 40 × 1 = 40,
   90/40 = 90 × 1/40 × 1 = 90/40
3. Likewise, for the 2nd fraction, since 8 × 5 = 40,
   81/8 = 81 × 5/8 × 5 = 405/40
4. Subtract the two like fractions:
   90/40 - 405/40 = 90 - 405/40 = -315/40
5. After reducing the fraction, the answer is -63/8

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