The starting price of a taxi in a certain city is 7 yuan (within 3 kilometers), and the average price per kilometer is 2.4 yuan for more than 3 kilometers. Xiaohua paid a total of 20.2 yuan for the taxi from home to Xinhua Bookstore. How many kilometers is it from Xiaohua's home to Xinhua Bookstore?
某市出租车起步价7元(3千米以内)，超过3千米，平均每千米2.4元，小华从家到新华书店共付车费20.2元．小华家到新华书店有多少千米？
<gadget id="calculator">20.2 - 7</gadget>
<output>13.2</output>

<gadget id="calculator">13.2 / 2.4</gadget>
<output>5.5</output>

<gadget id="calculator">5.5 + 3</gadget>
<output>8.5</output>

<result>8.5</result>