In a pile of steel pipes, there are 6 steel pipes in the bottom layer and 2 steel pipes in the uppermost layer. The difference between two adjacent layers is 1 steel pipe. How many steel pipes are there in total in this pile?
一堆钢管，最下层有6根，最上层有2根，每相邻的两层都相差1根，这堆钢管共有多少根
<gadget id="calculator">2 + 6</gadget>
<output>8</output>

<gadget id="calculator">6 - 2</gadget>
<output>4</output>

<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">8 * (5/2)</gadget>
<output>20</output>

<result>20</result>