Final answer:
On that particular day, 1895 gallons of premium gas and 5685 gallons of regular gas were sold.
Step-by-step explanation:
Let's assume the number of gallons of premium gas sold is x. Since three times as many gallons of regular as premium gas were sold, the number of gallons of regular gas sold would be 3x.
The cost of each type of gas can be calculated by multiplying the number of gallons sold by the price per gallon. So, the cost of regular gas would be 3x * $2.95, the cost of performance plus gas would be x * $3.05, and the cost of premium gas would be x * $3.15.
Based on the given information, the total cost of all the gas sold is $15,315. Therefore, we can write the equation:
3x * $2.95 + x * $3.05 + x * $3.15 = $15,315
Simplifying the equation, we get:
8.1x = 15315
Dividing both sides by 8.1, we find that x = 1895. Therefore, 1895 gallons of premium gas were sold, and 3 * 1895 = 5685 gallons of regular gas were sold. No information was provided about the number of gallons of performance plus gas sold.