Question

help me at your own expense,,,please

Answer 1

what do you need help with?

Answer 2

i am doing a question of bushels of wheat versus price. i need to construct a formula, finding the average rate of change(slope) and the y intercept(where x=0)

Answer 3

the question is in terms of how much consumers are willing to buy versus price.here is the table of values to begin with

Answer 4

1.0 bushels,in billions = 2.05
1.5bushels=1.75
2.0bushels=1.45
2.5bushels=1.15

Answer 5

need to find the slope and the b of y=mx+b

Answer 6

I'm assuming P is on the vertical axis again right?

Answer 7

the slope seems to be -0.3/0.5 or -3/5

Answer 8

correct jlangley

Answer 9

and S is now D

Answer 10

Yes, for demand!

Answer 11

so the change in values for both D and P are constant?

Answer 12

is seems to be constant

Answer 13

it*

Answer 14

ok because that is what i need to do the formula. a constant average rate of change

Answer 15

another way to find slope is (y2-y1)/(x2-x1)

Answer 16

using two sets of points

Answer 17

ok i got that. now i need an y-intercept. i think i know how to do it now but if you could tell me what you got and we'll compare.

Answer 18

does b=2.65?

Answer 19

no that cant be right

Answer 20

yes the y-intercept is 2.65

Answer 21

is the slope is constant that is what it would be

Answer 22

if*

Answer 23

so the formula according to my math is, y=-.6x+2.65

Answer 24

yes I believe so

Answer 25

ok and it asked me to add those points on to the same graph, just saying

Answer 26

Yes, if you've had economics background this is a basic graph of quantity demanded at various prices or a demand schedule as they call it.

So say we have y=mx+b, again. Your basic slope-intercept form.
Put this in terms of D and P.
P=mD+b

For slope we take your first two pairs of values on the table and place them into coordinate pairs in the form (x,y) or (D,P)
D P D P
(1.0, 2.05) and (1.5, 1.75)

So, m= change in y over change in x, or:
\[m=\frac{ y _{2}-y _{1} }{ x _{2}-x _{1} }\\m=\frac{ 1.75-2.05 }{1.5-1.0 }=-0.6\]

Now plug this into our equation P=mD+b
P=-0.6D+b

Alright, let's plug in a point to find b. Any point will work.
(D,P) = (1.0, 2.05)
P=-0.6D+b
(2.05)=-0.6(1.0)+b
2.05+0.6=b
b=2.65

Now, let's plug b, our y-intercept, back into our formula P=-0.6D+b"
b=2.65
P=-0.6D+b
P=-0.6D+2.65

Let's test plug any value of quantity demanded and solve for price or vice versa.

(D,P)=(2.5,1.15)

P=-0.6D+2.65
P=-0.6(2.5)+2.65
P=-1.5+2.65
P=1.15

It works!!!! :D

Answer 27

oh great! me and the other person were working it out but this is much more laid out. another part of the question is asking me why the curve should be decreasing. should i just say that as the price goes up people won't buy as much? seems logical

Answer 28

Exactly! Economics assumes that consumers make well-informed logical decisions. In their mind, they formulate a price that they decide is the maximum price they want to pay. They will not pay over that if they can keep from it, so quantity demanded tends to go down as price goes up. In other words, they are inversely related, and you can see it from the table. The value for D and P increase in opposite directions. So your graph looks similar to this .

Answer 29

that makes sense! and to find the equilibrium price, i would set the equations equal to each other right?

Answer 30

Pretty much! Equilibrium occurs where P=D!

Answer 31

alright so that ends another fun problem :p thanks!

Answer 32

No "problem"!

Answer 33

...lol