Smallville will import 2000 units.
Using the equations given, calculate supply and demand for that price and then find the difference between the 2 to see if you will need to import to meet supply or export to get rid of extra supply.
Find demand at the given price:
p =5000-.5Q
3000 = 5000- .5Q (subtract 5000 from both sides)
-2000 = -.5Q (now divide by -.5 on both sides)
Q = 4000
So at the Price of $3000, quantity demanded (Q) will be 4000
Now, find quantity supplied at the same price:
P = 1.5Q
3000 = 1.5 Q (divide both sides by 1.5)
Q= 2000
Compare these two numbers. At a price of $3000, we know there will be a demand of 4000 units and a supply of only 2000 units. To meet demand, Smallville must import 2000 units.