Question

A store had 150 laptops in the month of January. Every month, 20% of the laptops were sold and 10 new laptops were stocked in the store. Which recursive function best represents the number of laptops in the store f(n) after n months?

f(n) = 150 − 0.8 × f(n − 1) + 10, f(0) = 150, n > 0
f(n) = 0.2 × f(n − 1) + 10, f(0) = 150, n > 0
f(n) = 0.8 × f(n − 1) + 10, f(0) = 150, n > 0
f(n) = 150 + 0.8 × f(n − 1) + 10, f(0) = 150, n > 0

Answer 1

N. f(n)
0 150
1 .8 (150)+10
2. ......

The answer is c

hoping this helps

Answer 2

Option C is the correct answer.

Explanation:

Let us find the amount of laptops available.

n = 0, Laptops = 150

n = 1 , Laptops = 150 - 0.2 x 150 + 10 = 0.8 x 150 + 10 = 130

n = 2, Laptops = 130 - 0.2 x 130 + 10 = 0.8 x 130 + 10 = 114

So we have f(0) = 150.

f(1) = 0.8f(0)+10

f(2) = 0.8f(1)+10

Similarly f(n) = 0.8f(n-1)+10

Option C is the correct answer.