The students lined up, and Xiao Ming was among them. He counted the number of people, the number of people to his left is 70% of the total number of people, and the number of people to his right is 20% of the total number of people. Do you know which number Xiao Ming ranks from left to right?
同学们排成一行，小明也在其中．他数了数人数，排在他左面的人数是总人数的70%，排在他右面的人数是总人数的20%．你知道从左往右小明排在第几个吗？
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (7/10) - (1/5)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / (1/10)</gadget>
<output>10</output>

<gadget id="calculator">10 * (7/10)</gadget>
<output>7</output>

<gadget id="calculator">7 + 1</gadget>
<output>8</output>

<result>8</result>