Answers

Subtract 90/54 from 81/70

1^st number: 1 11/70, 2^nd number: 1 36/54

81/70 - 90/54 is -107/210.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 54 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 54 × 35 = 1890,
   90/54 = 90 × 35/54 × 35 = 3150/1890
4. Subtract the two like fractions:
   2187/1890 - 3150/1890 = 2187 - 3150/1890 = -963/1890
5. After reducing the fraction, the answer is -107/210

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