00:01
Okay, in this problem, we have been given an input -output matrix showing agriculture, manufacturing, and households, and a demand matrix d, showing how much of everything we need to have left over after our manufacturing process.
00:18
As you can see, i've already entered those matrices into a desmos application here on my computer.
00:25
You can tell from the icon this is a computer or graphing calculator problem.
00:31
So you can use whatever tool you are most comfortable with, either a calculator or a computer.
00:36
This is just one that i like to use.
00:38
I think it works very nicely.
00:40
Okay, so i have these matrices, but the real question is what do i do with them? so let's review what these matrices mean.
00:50
If i have a demand matrix d, that means that's the demand i have.
00:54
After i've manufactured whatever it is i'm doing, this is what i want to have as my final output.
01:01
Now, when i produce something, that's my matrix x.
01:05
And if manufacturing didn't cost anything, then what i produced would go to cover my demand, and d would equal x.
01:13
But that's not the case.
01:16
Manufacturing things costs something.
01:18
There is a cost involved.
01:22
And that cost is represented by ax.
01:24
A is how much manufacturing each of these things costs, how many units it costs, x is how many things are manufacturing.
01:33
So ax tells me my total cost involved in manufacturing x amount of each of these items.
01:40
So when i have my production matrix x, i subtract the cost it requires to make these things.
01:49
What i have left, that difference needs to be enough to cover my demand.
01:54
Okay...