The average height of 10 elementary school students is 1.5 meters, some of them are below 1.5 meters, their average height is 1.2 meters, and the average height of others higher than 1.5 meters is 1.7 meters, so how many students are at most exactly 1.5 m.
10位小学生的平均身高为1.5米，其中有一些低于1.5米的，他们的平均身高是1.2米，另一些高于1.5米的平均身高是1.7米，那么最多有多少位学生的身高恰好是1.5米．
<gadget id="calculator">10 - 5</gadget>
<output>5</output>

<result>5</result>