The non-staple food store shipped 400 kilograms of eggs, sold all the eggs (1/4) in the morning, and sold all the eggs (1/5) in the afternoon, what fraction of these eggs were sold in total?
副食店运来400千克鸡蛋，上午卖出全部鸡蛋的(1/4)，下午卖出全部鸡蛋的(1/5)，一共卖了这些鸡蛋的几分之几？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/4) + (1/5)</gadget>
<output>9/20 = around 0.45</output>

<result>9/20 = around 0.45</result>