The price of products may increase due to inflation and decrease due to depreciation. Derek is studying the change in the price of two products, A and B, over time.

The price f(x), in dollars, of product A after x years is represented by the function below.

f(x) = 72(1.25)^x

Question

The price of products may increase due to inflation and decrease due to depreciation. Derek is studying the change in the price of two products, A and B, over time.

The price f(x), in dollars, of product A after x years is represented by the function below.

f(x) = 72(1.25)^x

anonymous · Answer

Part A: Is the price of product A increasing or decreasing and by what percentage per year? Justify your answer. 

Part B: The table below shows the price f(t), in dollars, of product B after t years.

t (number of years)	1	 2	     3	            4
f(t) (price in dollars)	65   84.5   109.85   142.81

Which product recorded a greater percentage change in price over the previous year? Justify your answer.

anonymous · Answer

A. This relationship = (1.25)^x is what you get with a 25% per year price increase.

B. Take the ratios for succeeding years, e,g, 84.5/65, and see if any is greater than 1.25 true of product A.

anonymous · Answer

So the answer for part A is 25% increase?
And for part B, I got 1.3 for every difference. So the answer is product B has a greater percentage?

anonymous · Answer

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