Question

The cost of packing a box of chocolates is given by x2, where x is the number of chocolates (a box can never have fewer than 3 chocolates). If the weight of a box of chocolates is given by x + 2, what is the cost of packaging per weight unit?

Answer 1

x = number of chocolates >= 3
Cost of packaging, C = x^2
Weight of a box, W = x+2

Cost per weight unit is
C/W = x^2/(x+2)

Note that x >= 3
Create a table as shown below.

x C/W
------- ----------
3 1.80
4 2.67
5 3.57
6 4.50
7 5.44

Answer:

The minimum cost of packaging per unit is 1.80 for 3 chocolates. The cost increases as the number of chocolates in a box increases.