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

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:

Answer 1

@jcpd910 Help again please, Last one and im done lol

Answer 2

I Think A is increase

Answer 3

But dk %

Answer 4

f(x) = 72(1.25)x

Okay, we know that it is an increase because 72 * 1.25 is 90.

Answer 5

yes

Answer 6

Wait, one second...

Answer 7

ok

Answer 8

Ah, the difference is 18, so we divide 18 by 72 and multiply by 100. The percent increase is 25%.

Answer 9

So, to answer your question:
The price of Product A is increasing by 25% each year. We can justify this by multiplying 72 by 1.25, and then finding the difference between 72 and the sum of our equation. We then divide the difference by 72, and multiply by 100%. The product is our percent increase.

Answer 10

I don't see the table the next part is referring to.

Answer 11

ok sorry back

Answer 12

I need the table.

Answer 13

@jcpd910 how do i upload

Answer 14

And what's the question?

Answer 15

t (number of years) 1 2 3 4
f(t) (price in dollars) 65 84.5 109.85 142.81

Answer 16

Part B

Answer 17

The table below shows the price f(t), in dollars, of product B after t years:

Answer 18

Which product recorded a greater percentage change in price over the previous year? Justify your answer. @jcpd910

Answer 19

This is confusing. 'Which product' is asking about both products, or comparing them, but then 'previous year' is based on only a single product. I'll do it how I think they want it...

Answer 20

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

f(x) = 72(1.25)
Which product recorded a greater percentage change in price over the previous year? Justify your answer.

Answer 21

Does that help?

Answer 22

Correction on the function
f(x) = 72(1.25)^x

Answer 23

Not really, we already know it's a 25% increase each year.

Answer 24

But at least now I know it's compound.

Answer 25

So our next function is:
f(t) = 65(x)^t

Answer 26

Wait, no... better way to do this, what is it....

Answer 27

Oh, durhur.
84.5 - 65 = 19.5
19.5 / 65 = 0.3
0.3 * 100% = 30%

Answer 28

So Product B has a higher percent increase.

Answer 29

Thank you very much person

Answer 30

No problem person.

Answer 31

Well cya time for some Bf4 and Cod Lol