The students participate in sports performances and line up in square arrays with equal numbers of people: "I am the 15th from the front, the 6th from the back, the 7th from the left, and the 7th from the right." 8." How many students are there in this phalanx?
同学们参加运动会表演，排成每行人数相等的方阵："从前面数我是第15个，从后面数我是第6个，从左边数我是第7个，从右边数我是第8个．"这个方阵共有多少名同学？
<gadget id="calculator">6 - 1</gadget>
<output>5</output>

<gadget id="calculator">15 + 5</gadget>
<output>20</output>

<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">7 + 7</gadget>
<output>14</output>

<gadget id="calculator">20 * 14</gadget>
<output>280</output>

<result>280</result>