A taxi in a certain city charges 8 yuan within 3 kilometers and 1.7 yuan per kilometer after 3 kilometers. How much does it cost Mr. Zhang to ride for 7 kilometers?
某市的出租车在3千米及其以内收费8元，超过3千米后，每千米加收1.7元．张老师乘坐了7千米，要花多少元．
<gadget id="calculator">7 - 3</gadget>
<output>4</output>

<gadget id="calculator">4 * 1.7</gadget>
<output>6.8</output>

<gadget id="calculator">6.8 + 8</gadget>
<output>14.8</output>

<result>14.8</result>