40% of the number A is 20% of the number B, and the number B is 12, what is the number A?
甲数的40%是乙数的20%，乙数是12，甲数是多少．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(1/5) / (2/5)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">12 * (1/2)</gadget>
<output>6</output>

<result>6</result>