The taxi fare standard in a certain city is as follows: 12 yuan within 3km; 2.4 yuan per kilometer for more than 3km and within 10km; 3.6 yuan per kilometer for more than 10km (less than 1km is calculated as 1km). How much does it cost Uncle Li to take a taxi to a place 20km away from home?
某城市出租车收费标准如下：3km以内12元；超过3km且在10km以内的，每千米2.4元；超过10km，每千米3.6元(不足1km按1km计算)．李叔叔乘出租车到距离家20km的，一共要花多少钱？
<gadget id="calculator">10 - 3</gadget>
<output>7</output>

<gadget id="calculator">2.4 * 7</gadget>
<output>16.8</output>

<gadget id="calculator">20 - 10</gadget>
<output>10</output>

<gadget id="calculator">3.6 * 10</gadget>
<output>36</output>

<gadget id="calculator">12 + 16.8 + 36</gadget>
<output>64.8</output>

<result>64.8</result>