A wooden barrel with a bottom diameter of 5 decimeters is surrounded by a circle of steel bars, and the length of the weld is 3 centimeters. How long is this rod in centimeters?
在一个底面直径是5分米的木桶外面围一圈钢条，焊接处长3厘米．这根钢条全长多少厘米？
<gadget id="calculator">5 * 10</gadget>
<output>50</output>

<gadget id="calculator">3.14 * 50</gadget>
<output>157</output>

<gadget id="calculator">157 + 3</gadget>
<output>160</output>

<result>160</result>