project, complete its (1/9) every day, complete his ((())/(())) in 7 days, how many days to complete this project.
一项工程，每天完成它的(1/9)，7天完成他的((())/(()))，多少天完成这项工程．
<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">1 / (1/9)</gadget>
<output>9</output>

<result>9</result>