There are more than 200 chess pieces arranged in a square with n rows and n columns. A first takes 10 pieces from it, and B takes another 10 pieces from it, and so on in turn until all are taken. As a result, it was taken away by B for the last time. How many chess pieces did B take away?
有200多枚棋子摆成了一个n行n列的正方形，甲先从中取走10枚，乙再从中取走10枚，…，这样轮流取下去，直到取完为止．结果最后一次被乙取走．乙共取走了多少枚棋子．
<gadget id="calculator">12 * 10</gadget>
<output>120</output>

<gadget id="calculator">120 + 6</gadget>
<output>126</output>

<result>126</result>