The starting price of a taxi in a certain city is 3.00 yuan, and the farthest distance can be 2 kilometers. For a distance of more than 2 kilometers, an additional fee of 0.80 yuan per kilometer will be charged. Xiaodong took a taxi to his grandmother's house 7 kilometers away, how much should he pay at least?
某市出租车的起步价为3.00元，最远可到2千米的地方．超过2千米的路程，每千米加收0.80元．小东乘出租车去7千米外的外婆家，他至少应付多少车费？
<gadget id="calculator">7 - 2</gadget>
<output>5</output>

<gadget id="calculator">5 * 0.8</gadget>
<output>4</output>

<gadget id="calculator">3 + 4</gadget>
<output>7</output>

<result>7</result>