You deposit 300$ into an account that earns 4% simple annual interest. what is the balance of the account after 6 years?

4% of 300 is 12, so you get an extra $12 added to your account each year. Since you had it in there for 6 years that would be 12 x 6
So the answer is $372

For this you need to know what 4% of 300 is. I believe it is 12$. Then all you need to do is multiply 12 by 6 which gives us 72. Which you then add to 300 giving you your answer of $372. 

Hope this was helpful :)