The number A is twice the number B, and the number B is the number A.
甲数是乙数的2倍，乙数是甲数的多少．
<gadget id="calculator">1 * 2</gadget>
<output>2</output>

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

<result>1/2 = around 0.5</result>