Answered

Could someone help please?
The Sales S (in thousands of units) of a cleaning solution after X hundred dollars is spent on advertising are given:
S = 10(1 - e^(kx))
Now when $325 is spent on advertising 2300 units are sold.

(a)Complete by solving for k. (Round your answer to 4 decimal places)
k = _______

(b) What number of units that will be sold if advertising is raised up to $425
_______ Units.



Answer :

[tex]2.3=10(1-e^{3.25k}))\\ 2.3=10-10e^{3.25k}\\ 10e^{3.25k}=7.7\\ e^{3.25k}=0.77\\ 3.25k=\ln 0.77\\ k=\frac{\ln 0.77}{3.25}\\ k\approx-0.0804 [/tex]

[tex]S=10(1-e^{\frac{\ln 0.77}{3.25}\cdot4.25})\\ [/tex]

Calculating this is a pain in the ***, but as a result you get approximately 2.8949 which in thousands of units is 2894 (rounded down since you can't have a fraction of a unit).