Xiao Zhang and Xiao Li each typed a manuscript for 3 days. Xiao Zhang could type this manuscript every day (1/12), and Xiao Li could type this manuscript every day (1/18). How much is this manuscript?
打一份书稿，小张和小李各打了3天，小张每天可打这份稿件的(1/12)，小李每天能打这份稿件的(1/18)，他们共打了这份书稿的几分之几？
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 18</gadget>
<output>1/18 = around 0.055556</output>

<gadget id="calculator">(1/12) + (1/18)</gadget>
<output>5/36 = around 0.138889</output>

<gadget id="calculator">(5/36) * 3</gadget>
<output>5/12 = around 0.416667</output>

<result>5/12 = around 0.416667</result>