A project can be completed by Team A alone in 10 days, and Team B can complete the whole project (1/4) by working alone in 2 days. If the two teams work together for a few days, Team A can complete the remaining tasks in 1 day alone ． How many days did Team A and Team B work together?
一项工程，甲队单独做10天完成，乙队单独做2天可以完成全工程的(1/4)，如果两队先合做若干天后，甲队再单独做1天完成了剩余的任务．甲乙两队合做了多少天？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 - (1/10)</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/4) / 2</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/10) + (1/8)</gadget>
<output>9/40 = around 0.225</output>

<gadget id="calculator">(9/10) / (9/40)</gadget>
<output>4</output>

<result>4</result>