A school has 10 table tennis teams. In the regular season, every two teams play one game. How many games will there be in total?
某学校有10个乒乓队，常规赛中每两队一场，共要赛多少场？
<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">10 * (9/2)</gadget>
<output>45</output>

<result>45</result>