Final answer:
The equation that represents the cost, C, for x hours of use at the banquet hall is C = 27.5x.
Step-by-step explanation:
To determine the cost for x hours of use, we need to consider the rate of the banquet hall. Based on the given information, we know that the rental cost for 4 hours is $110. Since this is a linear relationship, we can determine the rate per hour by dividing the total cost by the number of hours. In this case, the rate is $110/4 = $27.50 per hour. Therefore, the equation that represents the cost, C, for x hours of use is C = 27.5x, option d.