A prism with dimensions [tex]x\times y\times z[/tex] has volume [tex]xyz[/tex] and surface area [tex]2xy+2yz+2xz[/tex].
So, the surface-area-to-volume ratio is
[tex]\dfrac{2xy+2yz+2xz}{xyz}=\dfrac{2\times4\times4+2\times4\times3+2\times4\times3}{4\times4\times3}=\dfrac{32+24+24}{48}=\dfrac53[/tex]
