Question

Postal regulations require that the length plus the girth of a package sent
can't exceed 108 inches. What is the largest possible volume of a rectangular
box with square ends that can be sent in the mail?

Answer 1

If the following expression is executed by the Mathematica program,

Maximize[ {L w h, 2w+2h<=108-L, 0<L<108, 0<2w<108, 0<2h<108}, {L,w,h} ]

then the answer presented is the following:

{ 11664, { L->36, w->18, h->18} }