The length and width of a rectangle are both prime numbers in decimeters, and the perimeter is 16dm. What is the area of this rectangle in square decimeters?
一个长方形的长和宽都是以"分米"为单位的质数，周长是16dm，这个长方形的面积是多少平方分米？
<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>