40% of A's number is B's (5/6), B's number is 12, what is A's number?
甲数的40%是乙数的(5/6)，乙数是12，甲数是多少．
<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(5/6) / (2/5)</gadget>
<output>25/12 = around 2.083333</output>

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

<result>25</result>