Mr. Huang took the students to a picnic, one rice bowl for one person, one vegetable bowl for two people, and one soup bowl for four people. He brought a total of 28 bowls, which were just finished. How many students are participating in the cookout?
黄老师带学生们去野炊，1人一个饭碗，2人一个菜碗，4人合用一个汤碗，他一共带了28个碗，正好分完．参加野炊的有多少名学生？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/2) + (1/4)</gadget>
<output>7/4 = around 1.75</output>

<gadget id="calculator">28 / (7/4)</gadget>
<output>16</output>

<result>16</result>