Answers

Subtract 42/40 from 12/54

1^st number: 12/54, 2^nd number: 1 2/40

12/54 - 42/40 is -149/180.

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,
   12/54 = 12 × 20/54 × 20 = 240/1080
3. Likewise, for the 2nd fraction, since 40 × 27 = 1080,
   42/40 = 42 × 27/40 × 27 = 1134/1080
4. Subtract the two like fractions:
   240/1080 - 1134/1080 = 240 - 1134/1080 = -894/1080
5. After reducing the fraction, the answer is -149/180

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