A tree is planted every 3 meters on both sides of an avenue, and a total of 302 trees are planted at both ends. How many meters is the total length of this avenue?
一条大道的两旁每隔3米栽一棵树，连两端共栽了302棵树，这条大道全长多少米．
<gadget id="calculator">302 / 2</gadget>
<output>151</output>

<gadget id="calculator">151 - 1</gadget>
<output>150</output>

<gadget id="calculator">150 * 3</gadget>
<output>450</output>

<result>450</result>