Question 197068
A consumer electronics company sells 6.7 million MP3 players per month at
 a price of $100 apiece; when the price is lowered tp$80, the company sells
 10.2 million players per month. How many MP3 players can the company expect
 to sell per month at a price of $75?
:
Assign the values as follows
x1 = 100; y1 = 6.7
x2 = 80; y2 = 10.2
;
Find the slope: m = {{{(10.2-6.7)/(80 - 100)}}} = {{{3.5/(-20)}}} = -.175
:
Find the equation using point/slope formula: y - y1 = m(x - x1)
y - 6.7 = -.175(x - 100)
y - 6.7 = -.175x + 17.5
y = -.175x + 17.5 + 6.7
y = -.175x + 24.2
:
How many MP3 players can the company expect to sell per month at a price of $75?
y = -.175(75) + 24.2
y = -13.125 + 24.2
y = 11.075 million sold at $75