How do you know when to use Linear Programming to solve a word problem?

1 Answer
Oct 19, 2017

Please see below.

Explanation:

Linear programming is a simple technique where we depict complex relationships through linear relations. These relations are constraints which put restrictions on values of the output, which are non-negative i.e. zero or positive. The results in such cases are generally located at points and then we find the most optimal point based on , at which the desired objective, which is again a linear relation among decision variables and is either maximised or minimised.

Hence, we use Linear Programming to solve a word problem when (i) we have linear relations; and (ii) certain function has to be maximized or minimized.

For example, let us have available x hours of labour and y cubic feet of wood, which we can use to make either tables or chair. A chair requires a1 hours of labour and a2 cubic feet of wood and a table requires b1 hours of labour and b2 cubic feet of wood. We have a profit of pa on chair and pb on table. How can we maximise profits.

Let the result be na chairs and nb tables. So our constraints are

na×a1+nb×b1x
na×a2+nb×b2y

We are to maximise na×pa+nb×pb

and non-negative outputs are na and nb.