There is a project, to be done alone, team A needs 10 days, team B needs 6 days. After the two teams have worked together for 3 days, what fraction of the project is left?
有一项工程，单独做，甲队需10天，乙队需6天．两队合作了3天后，还剩下这项工程的几分之几？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/10) + (1/6)</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">(4/15) * 3</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>