Question

A store had 50 bottles of olive oil. Each week, 40% of the olive oil bottles were sold and 20 new bottles arrived in shipments. Which recursive function best represents the number of bottles in the store, given that f(0) = 50?

f(n) = f(n − 1) ⋅ 0.6 + 20, n > 0

f(n) = 50 − f(n − 1) ⋅ 0.6 + 20, n > 0

f(n) = 50 − f(n − 1) ⋅ 0.4 + 20, n > 0

f(n) = f(n − 1) ⋅ 0.4 + 20, n > 0

Answer 1

f(1) = .6(50) + 20 = 30 + 20 = 50
f(2) = .6(50) + 20 = 50
f(3) = .6(50) + 20 = 50 forever and ever, good inventory planning

well try them, but you do not have to try many :)

Answer 2

Calculate the first few terms using your description.
(If 40% are sold, then 60% remain)

f(0) = 50
f(1) = .6(50) + 20 , looks like f(1) = .6(f(0)) + 20 = 50

Well, isn't that special, the number of bottles remains at 50

#1 and #3 yield the same result