If 8 basketball teams play in a single round robin, how many games will they play in total?
8支篮球队比赛，如果采用单循环赛制，一共要赛多少场．
<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>