(2/3) of 90 is equivalent to ((())/(())) of 40.
90的(2/3)相当于40的((())/(()))．
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(2/3) / 40</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">90 * (1/60)</gadget>
<output>3/2 = around 1.5</output>

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