In a ratio, the product of two inner terms is 3, one outer term is 9, and the other outer term is what.
在一个比例里，两个内项的积是3，一个外项是9，另一个外项是多少．
<gadget id="calculator">3 / 9</gadget>
<output>1/3 = around 0.333333</output>

<result>1/3 = around 0.333333</result>