# How do you find the cost of materials for the cheapest such container given a rectangular storage container with an open top is to have a volume of #10m^3# and the length of its base is twice the width, and the base costs $10 per square meter and material for the sides costs $6 per square meter?

##### 1 Answer

Let

Knowing that the lenght is twice the width means that

Knowing that the volume is fixed at

From the previous relation, we can express

Expressing all the three variables in terms of one is important, because now we have a problem which depends on a single variable: the area of the basis is

Since the base costs

So,

So, if you choose