It is known that the solution of equation 18-mx=12 is x=4, then m=how much.
已知方程18-mx=12的解是x=4，那么m=多少．
<gadget id="calculator">18 - 12</gadget>
<output>6</output>

<gadget id="calculator">6 / 4</gadget>
<output>3/2 = around 1.5</output>

<result>3/2 = around 1.5</result>