In the ratio, the two inner terms are known to be 0.6 and 9 respectively, so what is the product of the two outer terms.
在比例里已知两个内项分别是0.6和9，那么两个外项的积是多少．
<gadget id="calculator">0.6 * 9</gadget>
<output>5.4</output>

<result>5.4</result>