The fruit shop shipped a batch of 500 kg of fruit, of which apples accounted for 20% of the total weight of the fruit, and watermelons accounted for 40% of the total weight of the fruit. How many kilograms are the watermelon and apple together?
水果店运来一批水果共500千克，其中苹果占水果总重量的20%，西瓜占水果总重量的40%．西瓜和苹果一共多少千克？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">500 * (1/5)</gadget>
<output>100</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">500 * (2/5)</gadget>
<output>200</output>

<gadget id="calculator">100 + 200</gadget>
<output>300</output>

<result>300</result>