(2/5) of a number is (1/3), what is the formula for finding this number
一个数的(2/5)是(1/3)，求这个数的算式是多少
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

<gadget id="calculator">(1/3) / (2/5)</gadget>
<output>5/6 = around 0.833333</output>

<result>5/6 = around 0.833333</result>