Question

PLEASE HELP, TEST FRIDAY! (This is not a college question, I don't know why it says college)

The population of Iceland in 2008 was about 304,000 with an annual growth rate of 0.78%. Assume the growth rate is constant.

Question: Predict the population in 2020.

Answer 1

Ok, so do you know how to calculate a percent increase?

Answer 2

nope

Answer 3

If our percent is 0.78, let's divide it by 100 to get our decimal percent:
0.0078
Ok, now, let's add 1 because we are multiplying the value by 100.78%
1.0078

Answer 4

Do you follow me so far?

Answer 5

yes

Answer 6

Ok, we start in 2008.

Answer 7

Our population is 304,000.

Answer 8

How do we find what it will be in 2009?

Answer 9

I don't know, I'm sorry

Answer 10

wait um I know this isn't my place to say and it might be a little rude

Answer 11

No problem! All we have to do is multiply our value by our percent change. So, in this case:
population * percent change
304,000 * 100.79%
304,000 * 1.0079 = ?

Answer 12

but I have A LOT to know (4 projects, AP chemistry lab, about 50 hw questions and a lot more studying)

considering that this is just one question I only want to spend a little amount of time on this, max 10 minutes

please don't take this the wrong way, but I want to understand this questions ASAP

so if you don't mind please be straightforward with this question

Answer 13

anyways uh it's 306.40

Answer 14

Ok, no problem, I'll try to move a bit faster.

Answer 15

thanks for the consideration

Answer 16

304,000 * 1.0079 = 306,401.6

Answer 17

So, in 2009, the population will be 306,402

Answer 18

However, we want the population in 2020

Answer 19

We could write all these values, multiplying each consecutive one by 1.0079, but that would take too much time lol

Answer 20

So, instead, let's multiply:
304,000 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079 * 1.0079
one 1.0079 for each year we pass as we move towards 2020

Answer 21

Ok, that's a pretty crazy equation, so let's simplify it.

Answer 22

\[304,000 * 1.0079^{12}\]

Answer 23

Ok, are you allowed to use a calculator?

Answer 24

yes

Answer 25

oh that's the formula

Answer 26

=P(1+r)^t

Answer 27

correct :)

Answer 28

now you're getting it

Answer 29

So, evaluate 304,000*1.0079^12 on your calculator, and you have your answer. :D

Answer 30

334,104 people

Answer 31

cool it works, thank-you sir

Answer 32

Careful there, the exact answer is: 334,104.96228, which means we round up to 334,105

Answer 33

Other than that, you are absolutely welcome. ^-^