The fifth grade students do exercises, line up in a team of 12, and there are still 4 people missing, line up in a team of 15, and there are still 4 people missing. How many fifth graders are there at least?
五年级同学做操，排成12人一队，还缺4人，排成15人一队，还是缺4人．五年级同学最少有多少人？
<gadget id="calculator">2 * 2 * 3 * 5</gadget>
<output>60</output>

<gadget id="calculator">60 - 4</gadget>
<output>56</output>

<result>56</result>