You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.
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Question: Question: The difference between the place values of 7 and 3 in the number 527435 is

 Option A: 4

 Option B: 5

 Option C: 45

 Option D: 6970

 Option E: None

Answer: Option D


Question: Question: Rob traveled a distance of 30 km, covering the first 10 km in x minutes, the next 10 km in y minutes and the last 10 km in z minutes. If he totally took 3y minutes to cover the whole distance, then which of the following cannot be true? Assume x , y and z are different.

 Option A: z=3x

 Option B: x=3z

 Option C: y=2x

 Option D: x=2y

 Option E: y=3x

Answer: Option D


Question: Question: If f(x) = -*5 (x^4 - 1)/(x^2), what is f(1/x) in terms of f(x)?

 Option A: f(x

 Option B: -f(x

 Option C: 1/f(x

 Option D: 5f(x

 Option E: 2*f(x

Answer:
Option D