im stuck on one last question for my aplia assignment. I cant seem to solve it because i suck at algebra. Any help would be appreciated. I know you set QD=Qs then take the p and plug it into either equation. I cant seem to isolate properly.

(i dont have that question). But when i got this answer:

Q=300 billion units
P=$200/unit

and instead of making Qs=Qd; I made the prices equal

Its quite simple. Make the equations equal to Qs and Qd respectively, and then make them equal to each other and solve for P. Then input the P value into either equation and solve for Q.

I get P=200 and Q=300. Hope it helps.

Originally Posted by Fa11enAnge1

(i dont have that question). But when i got this answer:

Q=300 billion units
P=$200/unit

and instead of making Qs=Qd; I made the prices equal

I believe you cannot do that since that will give the quantity at the same price. You want to know the equilibrium of demand and supply market. So you have to rearrange to make it equal to Qs and Qd respectively and then equate them (Qs=Qd). Then you can find the solution.

Originally Posted by kamalprasher

I believe you cannot do that since that will give the quantity at the same price. You want to know the equilibrium of demand and supply market. So you have to rearrange to make it equal to Qs and Qd respectively and then equate them (Qs=Qd). Then you can find the solution.

umm I got the same answer you using that method (i just added in the units that the question mentioned). It should work because mathematically speaking you are finding the intersection point of the two functions.

this means that point the y-value of function1 = y-value of function2, and x-value of function1 = x-value of function2 (not saying that y=x) so whether you first figure out what that y-value is or what the x-value is - it doesnt matter.

My bad I misread the numbers. I thought you had them reversed, but I just noticed you gave quantity first. My mistake.

OP, please retake gr. 10 math.

Originally Posted by FireDragoonX

OP, please retake gr. 10 math.

they are a healthsci student

i havnt slept in 19 hours, i have 4 mid terms this week, give me a break (of that kit kat bar)

lol its ok. : D i know what you mean!!

P = 150 + (1/6)Q^S (1)
P = 350 - (1/2)Q^D (2)

The equilibrium price is when the quantity sold equals the quantity produced (Q^S = Q^D).

From (1), we see that Q^S = (P - 150) * 6 (3)
From (2), we see that Q^D = (350 - P) * 2 (4)

Setting (3) = (4) yields:

(P - 150) * 6 = Q^S = Q^D = (350 - P) * 2, or

3P - 450 = 350 - P =>
4P = 800 =>
P = 200 (dollars).

Now to solve for the quantity, we substitute into either (3) or (4):

Q^D = Q^S = (200 - 150) * 6 = 300 (billion).