It is planned to install a street lamp every 30 meters on one side of Guangming Road, a total of 71 lamps will be installed. Now instead of installing 43 energy-saving lamps, how many meters should the distance between two adjacent street lamps be changed?
计划在光明路的一侧每隔30米安装一盏路灯，一共要装71盏．现在改为安装43盏节能灯，相邻两盏路灯的间隔应改为多少米？
<gadget id="calculator">71 - 1</gadget>
<output>70</output>

<gadget id="calculator">70 * 30</gadget>
<output>2_100</output>

<gadget id="calculator">43 - 1</gadget>
<output>42</output>

<gadget id="calculator">2_100 / 42</gadget>
<output>50</output>

<result>50</result>