The students make breakfast and form a rectangular formation. Counting from the front and back, Xiao Ming is the 8th, and counting from the left and the right, Xiao Ming is the 5th. How many people are there in this rectangular formation?
同学们做早餐，排成一个长方形的方阵，从前、后数，小明都是第8个，从左、右数，小明都是第5个，这个长方形的方阵共有多少人？
<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">8 + 7</gadget>
<output>15</output>

<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<gadget id="calculator">15 * 9</gadget>
<output>135</output>

<result>135</result>