You can produce an objective function yourself. Usually it involves some sort of profit on each type of product, so this one is a tad unusual. You want to maximise the number of hampers made. Now, if you make
x basic,
y standard and
z luxury, then you make
x+y+z total, but you are told that you make the same number of standard hampers as you do luxury hampers so
y=z hence the total number made simplifies to
x+y+y=x+2y. This is what you want to maximise, so your objective function would now be
P=x+2y.