Uncle Wang bought several ornamental tropical fish for 64 yuan; Uncle Li also bought some of the same tropical fish for 80 yuan. If the unit prices of these tropical fish are the same, what is the highest unit price? (The unit price is an integer.)
王叔叔买了几条观赏热带鱼，花了64元；李叔叔也买了几条同样的热带鱼，花了80元．如果这些热带鱼的单价都相同，单价最高是多少元？(单价是整数．)
<gadget id="calculator">2 * 2 * 2 * 2</gadget>
<output>16</output>

<result>16</result>