certain tourist spot sells two types of tickets: children’s tickets and adult tickets. The price of children’s tickets is 30 yuan, and the price of adult tickets is 40 yuan. If you are a group, you can also buy group tickets with an average of 32 yuan per person. A tour group consisting of 8 families (each family has two adults or two adults and one child) travels to the scenic spot. If they buy group tickets and spend 120 yuan less than they buy individual tickets, the tour group How many people are there?
某旅游点有儿童票、成人票两种规格的门票卖，儿童票的价格为30元，成人票的价格为40元，如果是团体还可以买平均32元一位的团体票．一个由8个家庭组成的旅游团(每个家庭有两个大人或两个大人一个小孩组成)来景点旅游，如果他们买团体票以比他们各买各的票少花120元，这个旅游团一共有多少人？
<gadget id="calculator">40 * 2 * 8</gadget>
<output>640</output>

<gadget id="calculator">32 * 2 * 8</gadget>
<output>512</output>

<gadget id="calculator">640 - 512 - 120</gadget>
<output>8</output>

<gadget id="calculator">32 - 30</gadget>
<output>2</output>

<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 * 3</gadget>
<output>12</output>

<gadget id="calculator">8 - 4</gadget>
<output>4</output>

<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">12 + 8</gadget>
<output>20</output>

<result>20</result>