A scatterplot with a negative correlation implies that as one variable increases, the other variable tends to decrease.
Let's analyze the pairs:
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The weight of a package and the cost to mail the package: Generally, as the weight of a package increases, the cost to mail it also increases. This would likely show a positive correlation.
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The amount of gas in the tank of a car and the number of miles driven: As the amount of gas decreases, the number of miles driven typically decreases as well (up to the point where the tank runs out). This may not be a perfect correlation but could suggest a negative relationship, especially when considering fuel efficiency.
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The cost of a car and the number of tires it has: Most cars have four tires regardless of their cost. Therefore, there is no correlation to be found here.
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The cost of a telephone call and the length of the call: Generally, as the length of a call increases, the cost tends to increase as well (assuming a per-minute charge). This would show a positive correlation.
From these analyses, the second pair, "the amount of gas in the tank of a car and the number of miles driven," is the pair you would expect to show a negative correlation.