There are 13 water pipes in the lower layer and 3 in the upper layer. There are 11 layers in total. How many water pipes are there in total?
一堆水管，下层放了13根，上层放了3根，一共放了11层，水管共有多少根．
<gadget id="calculator">3 + 13</gadget>
<output>16</output>

<gadget id="calculator">11 / 2</gadget>
<output>11/2 = around 5.5</output>

<gadget id="calculator">16 * (11/2)</gadget>
<output>88</output>

<result>88</result>