If it is stipulated that A*B=5*A-(1/2)*B, where AB is a natural number, then 6*18=how much.
如果规定A*B=5*A-(1/2)*B，其中AB是自然数，那么6*18=多少．
<gadget id="calculator">6 * 5</gadget>
<output>30</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 18</gadget>
<output>9</output>

<gadget id="calculator">30 - 9</gadget>
<output>21</output>

<result>21</result>