Question

What is f(4) if f(1) = 3.2 and f(x + 1) = 2.5f(x) ?

A. 4.2


B. 8


C. 20


D. 50​

Answer 1

D. 50

Explanation:

To find the value of f(4) using the given information, we can use the recursive property of the function f(x) = 2.5f(x-1). Let's calculate it step by step:

Given:

f(1) = 3.2

f(x + 1) = 2.5f(x)

Using the recursive property, we can find f(2), f(3), and finally f(4).

f(2) = 2.5f(1) = 2.5 * 3.2 = 8

f(3) = 2.5f(2) = 2.5 * 8 = 20

f(4) = 2.5f(3) = 2.5 * 20 = 50

Therefore, f(4) = 50.