Marlene bought a circular rug with a radius of 3 feet for a total cost of $169. Which of the following is closest to the cost per square foot of the rug?

Calculating the cost per square foot as $6 would imply that the total area is around 28.17 square feet. This figure does not align with the actual area calculated using the rug's radius, which results in a much larger area of approximately 28.27 square feet. Hence, this choice underestimates the rug's actual cost per square foot.

Choosing $18 as the cost per square foot suggests that the total area would be significantly smaller than it is. If the cost per square foot were $18, the total area would need to be roughly 9.39 square feet, which does not correspond to the actual area of the rug. This value overestimates the cost per square foot based on the rug's actual dimensions.

A cost per square foot of $24 would indicate an even smaller area, approximately 7.04 square feet. This is far less than the actual area calculated for the rug. Thus, this choice significantly misrepresents the relationship between the total cost and the area of the rug.