Xiaoqing's family of four and his uncle's family of three share one electric meter, and the electricity bill in April is 280 yuan. How much should Xiaoqing's family pay for the electricity bill?
小青一家四口和伯伯一家三口合用一个电表，4月份电费280元．按人数分摊电费，小青家应交电费多少元？
<gadget id="calculator">4 + 3</gadget>
<output>7</output>

<gadget id="calculator">280 / 7</gadget>
<output>40</output>

<gadget id="calculator">40 * 4</gadget>
<output>160</output>

<result>160</result>