2010 B Micro FRQ #3

2010 B Micro FRQ #3

Watch me answer it here on youtube

https://youtu.be/4MmPMLCwKSQ

(A) The table below gives the quantity of good X demanded and supplied at various prices.

(i) Is the demand for good X relatively elastic, relatively inelastic, unit elastic, perfectly elastic or inelastic when the price decreases fro $30 to $20? Explain.

Elastic Cheat sheet is here.

First way to get this answer - - -

Second way to get this answer - - -     

 Total Revenue = P x Q

Total Revenue Test

Total Revenue at $30 price = Qd (1) x $30 = $30TR

Total Revenue at $20 price = Qd (3) x $20 = $60TR

Price decreased and Total Revenue increased = Relatively Elastic Demand

From the Elasticity Cheat Sheet

(ii) Is the supply of Good X relatively elastic, relatively inelastic, unit elastic, perfectly elastic or inelastic when the price decreases fro $30 to $20? Explain.

From the Cheat Sheet:

(iii) If a per-unit tax is imposed on good X, how will the tax be distributed between the buyers and sellers?

If the quantity supplied  does not change  when the price changes we assume that the good is perfectly inelastic. A perfectly inelastic supply implies that the supplier can't change the quantity of the good he produces. If a tax is imposed an a seller with a perfectly inelastic supply curve the seller will pay the total amount of the tax. 

(The one with the most inelasticity pays the burden of the tax) Know this...

(B) Assume that the income elasticity of demand for good Y is a -2. Using a CLG of the market for Good Y, show the effect of a significant increase in income on the equilibrium price of Good Y in the short-run.

You must understand that the YED, income elasticity of demand, when negative means that Good Y is an inferior good. 

From the Elasticity Cheat Sheet here.

From the Demand and Supply Cheat Sheet here

The "Y" in the cheat sheet above stands for Income. 

If Income (Y) increases then the quantity demanded of the good will decrease.

This is a bit confusing and perhaps I should rework the cheat sheet as actual Demand shifts to the left.

Demand decreases due to the rising incomes and Good Y being an Inferior good.

Remember from the Demand and Supply Cheat Sheet.

Inferior Good - (Y) Income increases then Demand (D) decreases

When Income increases the demand for Good Y decreases

2010 AP Micro FRQ#2

2010 AP Micro FRQ #2

Watch me answer it here

https://youtu.be/qnJ_Ut_Ev00 

(A) Using a CLG of the factor market for machines and the John Lamb Company, showing each of the following.

(i) The equilibrium rental price of machines in the factor market, labeled PR.

(ii) John Lamb's equilibrium rental quantity of machines, labeled as QL.

Understand that no matter if machines or labor we label the graphs the same. The college board is just checking to see if you know how to draw the Resource (factor) market graph.

Resource (Labor) Cheat Sheet here.

You also needed to know that a perfectly competitive (factor) market which will give us that perfectly elastic MRP curve for John Lamb's company.

(B) Assume the popularity for widgets declines decreasing the demand for widgets. What will happen to each of the following?

(i) Marginal product curve for machine hours.

Know what marginal product is:

from the Output and Costs, Cheat Sheet, here.

This is tricky -  understand that MP doesn't change for machines. The first machine makes 10 widgets an hour, the second machine makes 10 widgets and hour and so on...

(ii) Marginal Revenue Product curve for machine hours. Explain.

The MRP will decrease. As the demand for machines decreases, the price for the machines will fall. Since the formula for MRP = MP x P (of the good) and price of the good (widgets) decreases because the demand falls. The MRP shifts left.

From the Resource Costs Cheat sheet:

 

(C) John Lamb is employing the cost-minimisation combination of inputs (labor/machines). The marginal product of labor is 28 widgets per worker hour and the wage-rate is $14 an hour. The 

marginal product of the machine is 60 widgets per hour. What is the rental price per hour?

I did a blog post specifically on Least Cost Rule here.

Understand that the price of labor is the wage (MRC)

2010 Macro FRQ #3

2010 Macro FRQ #3

Mauricio Macri President of Argentina

(A) How will the transaction above affect Argentina's aggregate demand?

Argentina's imports will increase, therefore aggregate demand will decrease.

(B) Assume the US current account balance with Argentina is initially zero. How will the transaction above affect the US current account balance? Explain.

Balance of Payments Cheat Sheet here.

The US account balance will be a surplus as the US will have exported goods to Argentina. We will have a surplus in out current account and a deficit in the financial or capital account.

(C) Using a CLG of the FOREX market for the US dollar. show how a decrease in the US financial investment in Argentina affects each of the following.

(i) The supply of US dollars.

(ii) The value of the US dollar relative to the Peso.

Understand, that if the Argentinians are buying US goods they must go to the FOREX to buy US dollars as US suppliers do not accept Argentinian Pesos. So as Argentinians dump their money into the FOREX to buy US dollars the supply of US dollars in the FOREX decreases.

Obviously, when there is less of something the value of it increases. The value of the US dollar increases relative to the Peso.

(D) Suppose the inflation rate in the US is 3% and 5% in Argentina. What will happen to the value of the Peso relative to the US dollar as a result of the inflation rate difference? Explain.

Careful here as the college board is asking about the inflation rate (Price Level) not the interest rate as they do for so many of these problems.

If the US price level (inflation rate) is less than Argentinas then the prices of US goods are increasing at a slower rate than Argentinas goods. So relatively, US goods are going to be cheaper than the Argentinian goods. 

If US goods are cheaper than the Argentinian goods, relatively. Then Argentinians are going to purchase (import) more US goods. Again, they have to buy US dollars to purchase US goods. As they do this the supply of Argentinian Pesos increase in the FOREX market. A larger supply means that the Argentinian peso will loose value against the US dollar.

2010 B Macro FRQ #1

2010  B Macro FRQ #1

Watch me answer it here

https://youtu.be/LbJtYHi8lFs

2010 B Macro FRQ #2

2010  B Macro FRQ #2

Watch me answer it here

https://youtu.be/rgncLbqXjLk

Sells bonds = Contractionary = MS decreases

(A) Assume that banks in Sewell have no excess reserves. What is the effect of the central bank's action on the amount of customer loans that banks in Sewell can make?

Banks have no excess reserves, meaning they have no money to lend out. Then the FED sells bonds and bank customers take out even more cash to buy FED bonds. The bank is now having to borrow money from other banks to cover the checks written by its customers to buy those FED bonds. There is even less money in the system and no excess reserves to loan out. Loans decrease.

(B) Using a CLG of the money market, show they affects of the central banks actions on the nominal interest rate in Sewell.

(C) What is the effect of the Central bank's action on each of the following.

(i) PL

(ii) Real interest rate (RIR) Explain.

If the Central Bank uses a contractionary policy by  selling bonds then the nominal interest rate will increase as the money supply shrinks. As the money supply decreases and the nominal interest rate increases then there will be less consumption and investment which will decrease AD. As AD (aggregate demand) decreases the Price Level will fall. 

A quick way to know about the RIR is to know that nominal and real interest rates for the AP exam move in the same direction. So if the Nominal IR is increasing then the Real IR must also be increasing.

The central bank is contracting the money supply. The real interest rate is affected by the supply of money in the loanable funds market (commercial banks). If the FED is contracting the money supply then the supply of loanable funds is being extracted from the commercial banks. This lowers the supply of loanable funds and therefore the RIR will increase.

(D) Given your answer in part (C)(ii), how is the international value of the Sewell's currency, the Ono, affected. Explain.

Understand that when the AP College Board starts speaking about currency and RIR's together then we have to take the affects on the FOREX market.

So, if the RIR increases, foreigners will see the higher interest rates in the country of Ono, and want to invest in the country to get the higher interest rates. Profits attract investors. So if the RIR in Ono, increases and foreigners demand more currency from Ono in the FOREX. Then we will see the value of Ono's currency increasing. As demand for the Ono increases in the FOREX the value of the Ono will increase.

2010 B Macro FRQ #3

2010  B Macro FRQ #3

Notice (in the short-run) & (Explain each)

(A) An increase in the price of crude oil, an important natural resource.

Understand that crude oil is oil and therefore is a resource cost of business. Stagflation for the AP exam is usually caused by rising oil prices that shift the SRAS curve leftward. Raising costs (PL) and lowering RGDP.

(B) A technological change that increases the productivity of labor.

Productivity of labor implies that citizens of a country can produce more goods with the same resources due to technological change. This (in the short-run) is the graph that shows Growth.

(C) An increase in spending by consumers.

An increase in spending by consumers will increase the PL and increase the RGDP.

(D) The depreciation of the country's currency in the FOREX.

If a country's currency depreciates, the value of the currency falls, this will stimulate exports. Exports will increase as the currency value falls.

Why?

As the currency's value decreases foreigners can buy more of our goods. In essence our goods become relatively less expensive compared to foreign goods.

If Exports increase then AD increases, PL and RGDP increases.