Question 402565
I don't think I or any tutor will answer all 11+ parts to this question...but I'll get you started and you can finish the rest.


To find the linear equation, we have two ordered pairs (25, 60) and (15, 75) (here, the price is the x-variable, however normal demand curves list the number sold as the x-variable). The slope m is equal to {{{m = DELTA(y)/DELTA(x) = 15/-10 = -3/2)}}} so m = -3/2. To find the y-intercept replace m, as well as an ordered pair to obtain


60 = (-3/2)(25) + b --> 60 = -75/2 + b --> b = 195/2 = 97.5


The demand equation is therefore given by {{{p = (-3/2)x + 97.5}}}. You should be able to figure out the rest of the problems. Btw, part i) does not require trial and error, since the revenue is given by px, we have a quadratic equation that we can optimize using the vertex of the quadratic, or by the derivative.