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I have already tried sixty times five percent times three, & got nine. I don't think it is right but maybe it is I just need to know what to type in a calculator

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    After 1 month, you'll have 63. Then 105 % of that is 66.15 and then 105% of that is 69.46. – 2017-02-28
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    Tell me which bank that is! I'm considering to open an account there. – 2017-02-28
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    its on my homework – 2017-02-28
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    can you help @Bram28 – 2017-02-28

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Better to understand what's going on that have someone just tell you what to type into a calculator. Just standing back and thinking about the problem, you should be quite confident 9 dollars is not right. You started with 60 dollars, and are getting paid 5% interest compounded monthly? You should get all your money back, plus a little more.

In the first month, you get:

1.05 * \$60 = $63

Then you earn 5% interest on the \$63 dollars in the second month, which is:

\$63 * 1.05 = $66.15

Or put another way, you could express that as ($60 * 1.05) * 1.05

In the third month, you now earn 5% on 66.15 = 1.05 * 66.15 = 69.4575

This could be expressed as:

(($60 * 1.05) * 1.05) * 1.05

which is $60 * 1.05^3

(where ^3 means cubed) because there are three compounding periods.

Make sense?

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    What??????????????????? – 2017-02-28
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    @SagePosko that is an awful lot of question marks for what seems to me like a perfectly clear answer. What from the answer doesn't make sense? – 2017-02-28
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    Actually, after reading the question a second time, it says $60 put in a bank account every month. If you are putting 60 dollars in, plus earning 5% interest, you should be able to use the examples above,to work it out one month at a time. You start with 60 dollars, earn 5% (3 dollar) then put another 60 dollars in, which gives you 123 dollars at the start of the second month. Then what happens? – 2017-02-28
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    I don't know I am really stupid. i'm failing math with a D- – 2017-02-28