Answers

Subtract 42/27 from 81/70

1^st number: 1 11/70, 2^nd number: 1 15/27

81/70 - 42/27 is -251/630.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 27 is 1890
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1890
2. For the 1st fraction, since 70 × 27 = 1890,
   81/70 = 81 × 27/70 × 27 = 2187/1890
3. Likewise, for the 2nd fraction, since 27 × 70 = 1890,
   42/27 = 42 × 70/27 × 70 = 2940/1890
4. Subtract the two like fractions:
   2187/1890 - 2940/1890 = 2187 - 2940/1890 = -753/1890
5. After reducing the fraction, the answer is -251/630

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