Xiao Ming and Xiao Li share a total of 57 yuan, and Xiao Ming accounts for (1/3) of it. Later, Xiao Li bought a box of stationery, so that Xiao Ming accounts for (1/2) the total of the two. How much is this box of stationery?
小明和小李共有57元，小明占其中的(1/3)，后来小李买了一盒文具，这样小明占两人总数的(1/2)，这盒文具盒多少钱？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">57 * (1/3)</gadget>
<output>19</output>

<gadget id="calculator">57 - 19 - 19</gadget>
<output>19</output>

<result>19</result>