Xiaopang builds a triangle with plastic sticks, and every 3 plastic sticks build a triangle. After Xiaopang built 56 triangles, there are still 13 plastic sticks left. How many plastic sticks does Xiaopang have?
小胖用塑料棒搭三角形，每3根塑料棒搭一个三角形．小胖搭了56个三角形后，还剩13根塑料棒，小胖共有多少根塑料棒？
<gadget id="calculator">3 * 56</gadget>
<output>168</output>

<gadget id="calculator">168 + 13</gadget>
<output>181</output>

<result>181</result>