The correct answer is 6 ft
Explanation:
It is known the customer bought 3 identical rugs, which means the size and radio of each rug was the same. Moreover, the total this customer paid for the rugs was $1350, which is equivalent to $450 for each rug as $1350 ÷ 3 = $450.
Besides this, the black line in the graph shows at $450 (between 400 and 500 in the y-axis) the rugs have a ratio of 6 feet, which is shown in the x-axis as these two values intersect or align to form the black line. This means a carpet with a radius of 6ft costs $450, and therefore each of the rugs the customer bought had a radius of 6ft.