To complete page 2 of the "Classwork Book", Xiao Hua will need (2/15) hours, and Xiao Ming will need (1/6) hours. How many hours did Xiao Hua spend less than Xiao Ming?
完成《课堂作业本》的第2页，小华要用(2/15)小时，小明要用(1/6)小时．小华比小明少用多少小时？
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">(1/6) - (2/15)</gadget>
<output>1/30 = around 0.033333</output>

<result>1/30 = around 0.033333</result>