2. (10 points) A team of 8 people completed $\frac{1}{3}$ of a project in 30 days. Then, 4 more people were added to complete the remaining part of the project. Therefore, the total time to complete the project was $\qquad$ days.

The team of 8 people completed $\frac{1}{3}$ of a project in 30 days. Then, 4 more people were added to complete the remaining part of the project. Therefore, the total time to complete the project was $\qquad$ days.
【Analysis】Regarding this project as a unit "1", use “$\frac{1}{3} \div 30 \div 8=\frac{1}{720}$” to find the work efficiency of 1 person in 1 day, then the total work efficiency of 12 people is $\frac{1}{720} \times 12=\frac{1}{60}$. Calculate the remaining work volume, and then use "work volume ÷ work efficiency = work time" to find the time used later, and thus determine the total time used to complete this project.
【Solution】Solution: The work efficiency of one person is $\frac{1}{3} \div 30 \div 8=\frac{1}{720}$,
The total work efficiency of 12 people is $\frac{1}{720} \times 12=\frac{1}{60}$,
$$
\begin{array}{l}
=40+30 \\
=70 \text { (days) }
\end{array}
$$

Answer: It took a total of 70 days.
Therefore, the answer is: 70.