The sixth grade held a commendation meeting. There were 8 students participating in the meeting. Before the meeting, every two students shook hands with each other once. How many times did they shake hands in total?
六年级举办表彰会，有8名同学参会，会前每两名同学互相握一次手，共握多少次手．
<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">8 * (7/2)</gadget>
<output>28</output>

<result>28</result>