Answers

Subtract 81/7 from 20/54

1^st number: 20/54, 2^nd number: 11 4/7

20/54 - 81/7 is -2117/189.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 54 and 7 is 378
   
   Next, find the equivalent fraction of both fractional numbers with denominator 378
2. For the 1st fraction, since 54 × 7 = 378,
   20/54 = 20 × 7/54 × 7 = 140/378
3. Likewise, for the 2nd fraction, since 7 × 54 = 378,
   81/7 = 81 × 54/7 × 54 = 4374/378
4. Subtract the two like fractions:
   140/378 - 4374/378 = 140 - 4374/378 = -4234/378
5. After reducing the fraction, the answer is -2117/189

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