Answer:
744 in³
Step-by-step explanation:
Since you are filling the larger box with both rectangular prism and Styrofoam peanuts, you need to find the overall volume of the larger box and subtract the volume of the glass box to find the amount of space that the Styrofoam peanuts need to take up.
Volume (prism) = Bh, where B = area of the base, h = height
Larger Box: V = 10 x 10 x 15 = 1500 in³
Glass Box: V = 7 x 9 x 12 = 756 in³
1500 - 756 = 744 in³ of Styrofoam peanuts