College Algebra: reviewing for Final Exam!!
If $2500 is invested in the account that pays interest compounded continuously at a rate of 4%, how long will it take to double the investment?

Question

anonymous · Answer

I know the compounded continuously formula is $$A=Pe ^{rt}$$
However, I don't know what to do next.

jj123.33 · Answer

do the formula then multiply it by two cause its asking for double the investment

anonymous · Answer

So, once I plug it in, it would look like this?
$$A=2500e ^{0.04t}$$

jj123.33 · Answer

yes then you continue with the rest of the formula and after you get the answer multiply by  2

anonymous · Answer

That's the thing, I don't know how to continue from there. 
Is the next step this? $$2500=e ^{0.04t}$$

jj123.33 · Answer

so whats t

anonymous · Answer

I have no idea

jj123.33 · Answer

then after that you would multiply them to 2500

anonymous · Answer

It didn't tell me what t was

jj123.33 · Answer

t would be 2 because it wants to know the double the investment

anonymous · Answer

ooohhh

jj123.33 · Answer

yea

anonymous · Answer

I think I'm solving it wrong because I'm getting 2,708

jj123.33 · Answer

what is the numbers you pluged in

anonymous · Answer

I clicked 0.08, then e^x times 2500 on my calculator.

jj123.33 · Answer

you would multiply the 0.04 by 2500 then the answer by 2

anonymous · Answer

Wouldn't that be 200?

jj123.33 · Answer

i got 2,708 to is it a multi choice or something

anonymous · Answer

The answer is suppose to be 17.3 years.
I'm trying to find out how to solve the problem to get 17.3

jj123.33 · Answer

work the problem backwords but using the answer to get the numbers that you use to plug in the formula

anonymous · Answer

Not sure how to do that.