(2/3) of a number is 60, what is 50% of this number?
一个数的(2/3)是60，这个数的50%是多少．
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">90 * (1/2)</gadget>
<output>45</output>

<result>45</result>