(3/5) of a number is equal to (6/13) of 104, find this number.
一个数的(3/5)与104的(6/13)相等，求这个数．
<gadget id="calculator">6 / 13</gadget>
<output>6/13 = around 0.461538</output>

<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(6/13) / (3/5)</gadget>
<output>10/13 = around 0.769231</output>

<gadget id="calculator">104 * (10/13)</gadget>
<output>80</output>

<result>80</result>