Hey!
I will also show my work, to help you out, hope this answers the question (although it most likely will)...
Volume of a Rectangular Prism: V = LWH
Sally's Storage Container Volume (v1): 143mm^3
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For this one, we will consider this our storage container...
v2 = (4 (1/2))*(4 (1/2))*(6)
v2 = (4.5)*(4.5)*(6)
v2 = (20.25)*(6)
v2 = 121.5mm^3
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v1 - v2 = x; the difference between the two
143 - 121.5 = x
x = 21.5mm^3
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Sally's Storage Container is 21.5mm^3 bigger than our Storage Container...
