Answer:
13.6 years
Step-by-step explanation:
From the question;
We are needed to determine the time it took for the money to reach the given amount;
[tex]A=P(1-\frac{r}{100})^n[/tex]
Where n is the interest periods;
Therefore;
[tex]12800=7500(1-\frac{4}{100})^n[/tex]
Dividing both sides by 7500, we get;
[tex]1.7067=(1-\frac{4}{100})^n[/tex]
[tex]1.7067=(1.04)^n[/tex]
Introducing logarithms on both sides;
[tex]log1.7067=log(1.04)^n\\nlog1.04=log1.7067\\n=\frac{log1.7067}{log1.04} \\n=13.63[/tex]
Thus, n=13.6 years
Thus, it would take 13.6 years for the invested money to accumulate to 12800 dollars