00:01
So here we're talking about a monopoly, right? we know that the total fixed cost is equal to 30, and we know that the variable cost is equal to 5x, right? five per bag.
00:14
So for a, pretty straightforward, we are talking about average total cost.
00:20
Average total cost is going to be total cost divided by q, well, or by x, i should say.
00:27
I'm using x here for the number of bags.
00:31
So this would be 30 million, right? this is million plus 5x over x, which is equal to 30 million over x plus five, right? so here, no, no, this always falls as x increases, right, as quantity increases.
01:02
Right because the bigger x gets the smaller this number gets right x is on the denominator of the fraction so it never gets bigger is this a decreasing cost industry right so yes um yes decreasing cost cost industry right because the average total cost keeps falling as the firm gets bigger and bigger and bigger right it is always always always decreasing right so b, social optimal is to set marginal benefit is equal to marginal cost.
01:44
And the marginal cost here is five, right? because producing one more bag always costs five.
01:51
So the marginal cost is always five.
01:56
But if we do that, if so, firm loses 30 million, right? because it breaks even on costs and on variable costs, but it never covers its fixed costs.
02:13
If you only let it charge its marginal cost, it doesn't ever cover its fixed costs.
02:17
So the firm is going to lose $30 million, and it will want to exit, right? because it's losing money, right? so c.
02:27
C, we find out that price is equal to six.
02:31
Quantity demanded will be equal to 30 million.
02:36
Great.
02:36
We have some more information.
02:38
The profit here, okay, so it's going to be the six times the 30 million...