Answers

Subtract 81/70 from 30/40

1^st number: 30/40, 2^nd number: 1 11/70

30/40 - 81/70 is -57/140.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 40 and 70 is 280
   
   Next, find the equivalent fraction of both fractional numbers with denominator 280
2. For the 1st fraction, since 40 × 7 = 280,
   30/40 = 30 × 7/40 × 7 = 210/280
3. Likewise, for the 2nd fraction, since 70 × 4 = 280,
   81/70 = 81 × 4/70 × 4 = 324/280
4. Subtract the two like fractions:
   210/280 - 324/280 = 210 - 324/280 = -114/280
5. After reducing the fraction, the answer is -57/140

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