Answers

Subtract 20/54 from 81/42

1^st number: 1 39/42, 2^nd number: 20/54

81/42 - 20/54 is 589/378.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 54 is 378
   
   Next, find the equivalent fraction of both fractional numbers with denominator 378
2. For the 1st fraction, since 42 × 9 = 378,
   81/42 = 81 × 9/42 × 9 = 729/378
3. Likewise, for the 2nd fraction, since 54 × 7 = 378,
   20/54 = 20 × 7/54 × 7 = 140/378
4. Subtract the two like fractions:
   729/378 - 140/378 = 729 - 140/378 = 589/378
5. In mixed form: 1211/378

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