## anonymous 4 years ago How long it will take for \$300 to double when invested at 6% annual interest compounded twice a year? Answer: A)10.3 years B)11.7 years C)12.5 years D)13.1 years E)13.7 years This is my last question

1. anonymous

$600=300(1.06)^x$ solve for x

2. anonymous

no that is wrong

3. anonymous

$600=300(1+\frac{.06}{2})^{2x}$ solve for x

4. anonymous

$600=300(1.03)^{2x}$ $2=(1.03)^{2x}$ and right away you see that the 300 and 600 were not really part of the problem doubling time just means doubling time

5. anonymous

$(1.03)^{2x}=2$ $2x=\frac{\ln(2)}{\ln(1.03)}$ $x=\frac{\ln(2)}{2\ln(1.03)}$ then a calculator

6. anonymous

i get 11.7