Select ALL the correct answers.Marley owns a music store. The first week a new album was released, he sold 800 copies at his store. Each week after the release, the number of copies sold decreased by 11%.Select all the functions that can be used to find the number of copies sold, f(n), n weeks after the release.
Accepted Solution
A:
first week sold 800 copies ∴ at n=1 ⇒⇒⇒ f(1) = 800
Each week the number of copies sold decreased by 11%. ∴ at n = 2 ⇒⇒⇒ f(2) = 800 * (1-.11) = 800 * 0.89 = f(1) * 0.89 at n = 3 ⇒⇒⇒ f(3) = 800 * 0.89 *0.89 = 800 * 0.89² = f(1) * 0.89 * f(2) at n = 4 ⇒⇒⇒ f(4) = 800 * 0.89³ = f(1) * 0.89 * f(3) and so on .......
∴ [tex] f(n) = 800 * 0.89^{n-1} [/tex] Or which can be written as f(1) = 800 , f(n) = 0.89 * f(n-1) n ≥ 2