There used to be a place where the time was told by beating gongs, and the time was just a few times. For example, at 3 o'clock, just knock 3 times, and the time is 3 seconds. So, at 9 o'clock, how many seconds does it take to strike the gong?
以前有一个地方，专门靠敲锣来报时，几点就敲几下．比如，3点的时候，就敲3下，用时为3秒．那么，9点的时候，需要用多少秒来敲锣．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">9 - 1</gadget>
<output>8</output>

<gadget id="calculator">(3/2) * 8</gadget>
<output>12</output>

<result>12</result>