Question

Alexis has a savings account that earns 2.1% interest compounded daily. If she opened the account 17 years ago with a deposit of $2,914.72, how much interest has Alexis earned?

$1,235.15

$1,250.48

$2,975.93

$4,165.20

Answer 1

Same compound interest formula as the last question
P=2914
r= 0.021
n=365
t=17

so:
A= 2914.72(1+0.021/365)^(365*17)

Answer 2

Remove the 1 and the division over 365 (Not really sure about why this is in your formula, care to explain?) to get how much she's earned.

Answer 3

Oh yeah it's earned... just subtract the initial amount. ANd the 365 is correct, it's compounded daily.

Answer 4

I got 3136.3...

Answer 5

I think you're making mistakes on your calculator...

https://www.google.com/search?q=2914.72(1%2B0.021%2F365)%5E(365*17)&oq=2914.72(1%2B0.021%2F365)%5E(365*17)&aqs=chrome..69i57&sourceid=chrome&espv=210&es_sm=93&ie=UTF-8

now subtract the initial amount 2914.72 to find the interest

Answer 6

http://en.wikipedia.org/wiki/Compound_interest#Simplified_calculation

I think you're using the compound interest equation, which I'm pretty sure is wrong, as it doesnt give you the total amount earned.

The simplified calculation gives you the total earned when you substract the one.
Earned money is FV - PV.

Answer 7

Although, I've never taken a class in statistics, so I could be totally and absolutely wrong. :D

Answer 8

To get amount earned you subtract the initial amount, that's all.

Answer 9

someone lead me to the answer o.o

Answer 10

It's above brittney... A= 2914.72(1+0.021/365)^(365*17)

then subtract the initial 2914.72

Answer 11

using this: http://qrc.depaul.edu/studyguide2009/notes/savings%20accounts/Compound%20Interest_files/image002.gif

Answer 12

http://upload.wikimedia.org/math/e/0/c/e0ca87a82c591a0e0610792963751fd5.png

that formula is the same as the one i used @Lessis except i is the interest rate divided by the compounding number, 365, and n is the number of times compounded, 365*years.

Answer 13

You also can't just subtract the 1; it's inside the brackets with an exponent. You need the final amount to find the amount earned.

Answer 14

I got 1250 :(

Answer 15

haha that is correct, why a sad face??

Answer 16

It is??? YAYYY

Answer 17

Yeah, you're right. Sorry for the confusion. D: (I also thought the exponent was only affecting r/n )

Answer 18

I'm learning lol

Answer 19

haha yes! don't always be sad when you get an answer! haha be confident that you're right! except... don't use your phone as a calculator anymore.

Answer 20

lol I used a calculator for my last calculation

Answer 21

Do that more often then :) phones aren't good for complex stuff unless you're very careful about parentheses