Install street lights on both sides of a street, one every 50 meters (both ends must be installed), a total of 82 street lights should be installed. How long is this street in meters?
在一条街道的两侧安装路灯，每隔50米安一盏(两端都要安装)，一共要安装82盏路灯．这条街道全长多少米？
<gadget id="calculator">82 / 2</gadget>
<output>41</output>

<gadget id="calculator">41 - 1</gadget>
<output>40</output>

<gadget id="calculator">40 * 50</gadget>
<output>2_000</output>

<result>2_000</result>