Xiaohua participates in a gymnastics performance, and is ranked in the center of a square team, counting from front to back, left, right, and fifth. How many people participated in the gymnastics performance?
小华参加体操表演，排在一个正方形队伍的中心位置，从前后左右数都是第5位，参加体操表演的一共有多少人．
<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">9 * 9</gadget>
<output>81</output>

<result>81</result>