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: If x, y, and z are negative integers and 3x - 3y = -3z, then which of the following statements must be true?
I. x > y
II. x > y > z
III. x = z

 Option A: I and II

 Option B: I only

 Option C: II only

 Option D: III only

 Option E: None

Answer: Option B


Question: Question: A car dealership has 40 cars on the lot, 30% of which are silver. If the dealership receives a new shipment of 80 cars, 40% of which are not silver, what percentage of total number of cars are silver?

 Option A: 35%

 Option B: 37.5%

 Option C: 45%

 Option D: 47.5%

 Option E: 50%

Answer: Option E


Question: Question: What is the greatest positive integer x such that 3^x is a factor of 9^7?

 Option A: 5

 Option B: 14

 Option C: 10

 Option D: 20

 Option E: 30

Answer:
Option B