Answer:
12%
Explanation:
You are going to want to use a modified compound interest formula, as shown below. This version of the compound interest formula is what you use to solve for the interest rate.
![r=n[((A)/(P))^(1/nt)-1]](https://img.qammunity.org/2021/formulas/mathematics/high-school/u2inhsegnmz60jloik0frlgkcgb2eg5cqg.png)
r = interest rate (decimal)
n = numbers of times compounded (annually)
A = total amount
P = principal amount
t = time (years)
Now, lets plug in the values:
![r=1[((6,000)/(3,000))^(1/(1)(6))-1]](https://img.qammunity.org/2021/formulas/mathematics/high-school/ip9tt4k4ifsfo2ihqrkt7p8dv6i0ckaatd.png)

Next, multiply r by 100 to get our answer:

The last step is to round our answer to the nearest whole number:
12.246 -> 12