It is known that the middle term of the ratio between 4 and m is 6, then m=how much.
已知4与m的比例中项是6，那么m=多少．
<gadget id="calculator">6 * 6</gadget>
<output>36</output>

<gadget id="calculator">36 / 4</gadget>
<output>9</output>

<result>9</result>