During the "October" Golden Week, a bookstore reduced the price of a set of children's books priced at 40 yuan by 20%, and raised the price by 20% after the holiday. How much is the price of this set of children's books?
在"十一"黄金周期间，某书店把一套价格为40元的儿童读物降价20%出售，假期过后，又提价20%，这时这套儿童读物的价格是多少元？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">40 * (4/5) * (6/5)</gadget>
<output>192/5 = around 38.4</output>

<result>192/5 = around 38.4</result>