There are 25 sixth-grade students participating in the science and technology group, 7 more than twice the number of fifth-grade students. How many people participate in the fifth-grade science and technology group? (solution by equation)
六年级同学参加科技小组的有25人，比五年级参加人数的2倍还多7人，五年级参加科技小组的有多少人？(用方程解)
<gadget id="calculator">25 - 7</gadget>
<output>18</output>

<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<result>9</result>