There is an existing project. Team B first worked on it for 1 day, and then Team A and Team B cooperated for another 2 days to complete the project. The working efficiency ratio of Team A and Team B is 3:2. How many days will it take to complete the work if the entire Engineering Team A is alone?
现有一项工程，乙队先做了1天，甲队和乙队合作又做了2天才完工，甲队、乙队工作效率比是3：2．若整个工程甲队单独，做完这项工作要多少天？
<gadget id="calculator">2 + 2</gadget>
<output>4</output>

<gadget id="calculator">4 / 1</gadget>
<output>4</output>

<result>4</result>