It is known that x and y are inversely proportional, when x=5, y=8.5, when y=17, x=how much.
已知x和y成反比例，当x=5时，y=8.5，当y=17时，x=多少．
<gadget id="calculator">5 * 8.5</gadget>
<output>42.5</output>

<gadget id="calculator">42.5 / 17</gadget>
<output>2.5</output>

<result>2.5</result>