Heyo! I hope your day is going well! I hope I can help you understand this a bit better!
First things first we have to figure out the total volume of the flower box. To do this we do a simple multiplication problem, 3*4*9, or length*width*height. 3*4 is 12, and then 12*9 is 108. So our total volume for the flower box is 108 cubic feet.
Lucy only wants to fill half of her flower box, so we are going to go ahead and divide our total volume, 108 cubic feet, by 2. Our answer here is 54 cubic feet.
The soil Lucy wants to buy is 1.65 for each cubic foot, meaning we should multiply 1.65 and 54.Our final answer is 89.1!