Uncle Zhang has 240 kilograms of watermelons. He sold 36 kilograms in the morning and 45 kilograms in the afternoon. How many kilograms did he sell in total?
张伯伯有240千克西瓜，上午卖了36千克，下午卖了45千克，一共卖了多少千克？
<gadget id="calculator">36 + 45</gadget>
<output>81</output>

<result>81</result>