Xiao Ming helped his mother sell watermelons. He sold 240 kilograms in the morning, for a total of 168 yuan, and 570 kilograms in the afternoon. How much more did you sell in the afternoon than in the morning?
小明帮妈妈卖西瓜，上午卖出240千克，共卖得168元，下午卖出570千克．下午比上午多卖了多少元？
<gadget id="calculator">168 / 240</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">570 - 240</gadget>
<output>330</output>

<gadget id="calculator">(7/10) * 330</gadget>
<output>231</output>

<result>231</result>