1. BU-224 Micro Economics – Week 6 Seminar
Welcome to
BU-224 Micro Economics – Week 6 Seminar

2. Overview Welcome Review of Week 5 Material Questions Unit 6 Material
Preview of Unit 7
End

3. Unit 5 Material Consumer Theory – “Rational Consumer”
Diminishing Marginal Utility

4. Consumption Possibilities
The budget line separates combinations that are affordable from combinations that are unaffordable.

5. Consumption Possibilities

6. Consumption Possibilities
Changes in Prices
If the price of one good rises when the prices of other goods and the budget remain the same, consumption possibilities shrink.
If the price of one good falls when the prices of other goods and the budget remain the same, consumption possibilities expand.

7. Consumption Possibilities
Shows the effect of a fall in the price of water. On the initial budget line, the price of water is $1 a bottle (and gum is 50 cents a pack), as before.

8. Consumption Possibilities
When the price of
water falls from $1 a bottle to 50¢ a bottle, the budget line rotates outward and becomes less steep.

9. Questions

10. Overview Welcome Review of Week 5 Material Questions Unit 6 Material
Preview of Unit 7
End

11. Unit 6 Material Marginal Analysis Production Function
Homework Assignment
Discussion

12. Marginal Analysis
Marginal analysis is used to assist people in allocating their scarce resources to maximize the benefit of the output produced.
Simply getting the most value for the resources used.

13. (Marginal = the next unit)
Marginal Analysis
Marginal analysis: The analysis of the benefits and costs of the marginal unit of a good or input.
(Marginal = the next unit)

14. Marginal Analysis
A technique widely used in business decision-making and ties together much
of economic thought.
In any situation, people want to maximize net benefits:
Net Benefits = Total Benefits - Total Costs

15. Marginal Analysis
To do marginal analysis, we can change a variable, such as the:
quantity of a good you buy,
the quantity of output you produce, or
the quantity of an input you use.
This variable is called the control variable .

16. Marginal Analysis

17. Marginal Analysis
Marginal analysis focuses upon whether the control variable should be increased by one more unit or not.

18. Marginal Analysis 1. Identify the control variable (cv).
2. Determine what the increase in total benefits would be if one more unit of the control variable were added.
This is the marginal benefit of the added unit.

19. Marginal Analysis
3. Determine what the increase in total cost would be if one more unit of the control variable were added.
This is the marginal cost of the added unit.

20. Marginal Analysis
4. If the unit's marginal benefit exceeds (or equals) its marginal cost, it should be added.

21. Marginal Analysis Because:
Marginal Benefit = Increase in Total Benefits
per unit of control
variable
TR / Qcv = MR
where cv = control variable

22. Marginal Analysis Marginal Cost = Increase in Total Costs
per unit of control
variable
TC / Qcv = MC

23. Marginal Analysis So: Change in Net Benefits =
Marginal Benefit - Marginal Cost

24. Marginal Analysis
When marginal benefits exceed marginal cost, net benefits go up.
So the marginal unit of the control variable should be added.

25. A firm's net benefit of being in business is PROFIT.
Marginal Analysis
A firm's net benefit of being in business is PROFIT.
The following equation calculates profit:
PROFIT = TOTAL REVENUE - TOTAL COST

26. Marginal Analysis Where: TR = (Poutput X Qoutput) n
TC =  (Pinputi X Qinputi)
i=1
Assume the firm's control variable is the output it produces.

27. Marginal Analysis
International Widget is producing fifty widgets at a total cost of $50,000 and is selling them for $1,200 each for a total revenue of $60,000.
If it produces a fifty-first widget, its total revenue will be $61,200 and its total cost will be $51,500.

28. Marginal Analysis
Should the firm produce the fifty-first widget?

29. Marginal Analysis The fifty-first widget's marginal benefit is $1,200
($61,200 - $60,000) / 1
This is the change in total revenue from producing one additional widget and is called marginal revenue.

30. Marginal Analysis The firm's marginal cost is $1,500
($51,500 - $50,000) / 1
This is the change in total cost from producing one additional widget.
This extra widget should NOT be produced because it does not add to profit:

31. Marginal Revenue - Marginal Cost
Marginal Analysis
Change in Net Revenue (Benefit) =
Marginal Revenue - Marginal Cost
- $300 = $1,200 - $1,500

32. Marginal Analysis Qcv Qwidgets TR TR TC TC 50 60,000 50,000
, ,000
, ,500
, ,500
MR = TR / Qcv = $1,200 / 1 = $1,200
MC = TC / Qcv = $1,500 / 1 = $1,500

33. Marginal Analysis
What is the minimum price consumers would have to pay to get a 51st Widget produced?
Consumers would have to pay at least $1,500 for the extra widget to get the producer to increase production.

34. Marginal Analysis
Marginal analysis forms the basis of economic reasoning.
To aid in decision-making, marginal analysis looks at the effects of a small change in the control variable.

35. Marginal Analysis
Each small change produces some good (its marginal benefit) and some bad (its marginal cost).
As long as there is more "good" than "bad", the control variable should be increased (since net benefits will then be increased).

36. Production Function

37. Production Function

38. Production Function

39. Production Function

40. Week 6 Assignment
The accompanying table shows a boat manufacturer’s total cost of producing boats.

41. Week 6 Assignment What is this manufacturer’s fixed cost?
For each level of output, calculate the variable cost (VC). For each level of output except zero output, calculate the average variable cost (AVC), average total cost (ATC), and average fixed cost (AFC)

42. Discussion
Suppose a business experiences a sudden increase in its fixed costs. For example, suppose property taxes increase dramatically. What impact, if any, will this have the firm's AFC (average fixed cost), AVC (average variable cost), ATC (average total cost) and MC (marginal cost) and therefore these cost curves? Why?

43. Thank you for attending. I look forward to seeing you next week!