The stationery store buys 200 schoolbags at a price of 10 yuan each, and sells them at a price of 16 yuan each. When a part is sold, the remaining schoolbags are sold at a 20% discount. When the schoolbags are sold out, the store makes a total profit of 1040 yuan. How many schoolbags are sold at a 20% discount?
文化用品商店以每个10元的价格购进200个书包，卖出时每个标价16元，当卖了一部分后，剩下的书包打八折出售．书包卖完时这个商店共盈利1040元，其中打八折卖出的书包有多少个？
<gadget id="calculator">200 * 16</gadget>
<output>3_200</output>

<gadget id="calculator">200 * 10</gadget>
<output>2_000</output>

<gadget id="calculator">3_200 - 2_000 - 1_040</gadget>
<output>160</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">16 * (4/5)</gadget>
<output>64/5 = around 12.8</output>

<gadget id="calculator">10 - 10 - (64/5)</gadget>
<output>-64/5 = around -12.8</output>

<gadget id="calculator">16 + (-64/5)</gadget>
<output>16/5 = around 3.2</output>

<gadget id="calculator">160 / (16/5)</gadget>
<output>50</output>

<result>50</result>