Answers

Subtract 81/56 from 42/30

1^st number: 1 12/30, 2^nd number: 1 25/56

42/30 - 81/56 is -13/280.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 30 and 56 is 840
   
   Next, find the equivalent fraction of both fractional numbers with denominator 840
2. For the 1st fraction, since 30 × 28 = 840,
   42/30 = 42 × 28/30 × 28 = 1176/840
3. Likewise, for the 2nd fraction, since 56 × 15 = 840,
   81/56 = 81 × 15/56 × 15 = 1215/840
4. Subtract the two like fractions:
   1176/840 - 1215/840 = 1176 - 1215/840 = -39/840
5. After reducing the fraction, the answer is -13/280

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