Answer:
The volume in such a package is 27648 in³
Step-by-step explanation:
Consider the provided information.
Postal regulations specify that a parcel sent by priority mail may have a combined length and girth of no more than 144 in.
Let the dimension are x by x by y.
Where x is the variable for the square base package and y is the variable for length.
Thus l=x, b=x and h=y
Then the volume of the box is: (∵V=lbh)
The maximum combined length and girth is 144.
Therefore,
Substitute the value of y in volume of the box.
Substitute V'(x)=0.
Now apply second derivative test.
(Min)
(Max)
Hence, the maximum volume is at x=24
If x=24 then
Substituting value of x = 24 and y = 48 gives 27648.
Hence, the volume in such a package is 27648 in³