To solve this problem, we need to determine the amount of extra money a customer will need to pay when ordering 48 tires, based on the given ratio of 3 tires to a $6 increase.
Let's set up a proportion to find the extra money needed:
3 tires = $6
48 tires = x
To solve for x, we can cross-multiply and divide:
3x = 6 * 48
3x = 288
x = 288 / 3
x = 96
Therefore, the customer will need to pay an extra $96 when ordering 48 tires. The correct answer is option d. 96.