Answers

Subtract 81/28 from 15/42

1^st number: 15/42, 2^nd number: 2 25/28

15/42 - 81/28 is -71/28.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 28 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 42 × 2 = 84,
   15/42 = 15 × 2/42 × 2 = 30/84
3. Likewise, for the 2nd fraction, since 28 × 3 = 84,
   81/28 = 81 × 3/28 × 3 = 243/84
4. Subtract the two like fractions:
   30/84 - 243/84 = 30 - 243/84 = -213/84
5. After reducing the fraction, the answer is -71/28

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