(2/5) of A is equal to (5/6) of B, and B is the number of A.
甲数的(2/5)等于乙数的(5/6)，乙数是甲数的多少．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">(2/5) / (5/6) / 1</gadget>
<output>12/25 = around 0.48</output>

<gadget id="calculator">1 * (12/25)</gadget>
<output>12/25 = around 0.48</output>

<result>12/25 = around 0.48</result>