Use a 16 decimeter long iron wire to make an iron ring, the joint is 0.3 decimeter, what is the diameter of this iron ring?
用一根16分米长的铁丝做一个铁圈，接头处是0.3分米，这个铁圈的直径是多少分米？
<gadget id="calculator">16 - 0.3</gadget>
<output>15.7</output>

<gadget id="calculator">15.7 / 3.14</gadget>
<output>5</output>

<result>5</result>