(5/8) of 40 meters is exactly ((())/(())) of 50 meters.
40米的(5/8)刚好是50米的((())/(()))．
<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">(5/8) / 50</gadget>
<output>1/80 = around 0.0125</output>

<gadget id="calculator">40 * (1/80)</gadget>
<output>1/2 = around 0.5</output>

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