To find out how much Maya should actually be charged for the rocks, we need to calculate the total cost based on the price per ton and the amount of tons she needs.
Maya needs to buy 10.4 tons of rocks, and each ton costs $32.90.
Total cost = (price per ton) × (number of tons)
Total cost = $32.90 × 10.4
Calculating that:
Total cost = $342.16
So, Maya should actually be charged $342.16. The correct answer is c. 342.16.