Answers

Subtract 90/40 from 15/54

1^st number: 15/54, 2^nd number: 2 10/40

15/54 - 90/40 is -71/36.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 54 and 40 is 1080
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1080
2. For the 1st fraction, since 54 × 20 = 1080,
   15/54 = 15 × 20/54 × 20 = 300/1080
3. Likewise, for the 2nd fraction, since 40 × 27 = 1080,
   90/40 = 90 × 27/40 × 27 = 2430/1080
4. Subtract the two like fractions:
   300/1080 - 2430/1080 = 300 - 2430/1080 = -2130/1080
5. After reducing the fraction, the answer is -71/36

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