Economics

galwayu

The demand function for mobile phones in an urban market is represented by the equation: P= 400 - 12Qd, and the corresponding supply function is P= 100 + 8Qs, where P is price in Euros (€s) and Qd, Qs are the number of mobile phones bought and sold per month expressed in thousands of units.
Could someone write out a solution please.

Delta Kilo

Do your own homework!

galwayu

its not homework its a previous exam question I cant work out.

Polar Ice

First year mirco?
You haven't stated what the question is. Are you trying to find the equilibrium?

Qs is quantity supplied and Qd is quantity demanded.
There are both just levels of demand so swap both for something like x.
P= 400 - 12x
P= 100 + 8x

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100 + 8x = 400 - 12x
20x=300
x=15

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P=100+8(15)
P=100+120
P=220

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The equilibrium where supply equals demand is at the level where demand is 15 units and price is 220

galwayu

Thanks a million Polar Ice.Yes 1st year micro looking for equilibrium price and quantity.Thanks again:D

billyknowsbest

Can anybody help me with this?
- a firm has a fixed amount of resources they can either make 800,000 cars and no tractors OR 200,000 tractors and no cars
-Can the PPC be linear here?
- How many tractors can the firm make when they produce 100,000 cars, 400,000 cars, 600,000 cars
- What would be the opportunity cost of 300,000 cars, 700,000 cars, 100,000 tractors and 50,000 tractors
I have done it but all my answers look odd, to say the least, I'm in adult ed. and am really not at ease doing claculations- many thanks in advance