A piece of triangular glass has a base of 12.6dm and a height of 5dm. The price of glass per square decimeter is 0.7 yuan. How much does it cost to buy this piece of glass?
一块三角形的玻璃，它的底是12.6dm，高是5dm，．每平方分米的玻璃价格是0.7元，买这块玻璃需要多少钱？
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">12.6 * (5/2)</gadget>
<output>31.5</output>

<gadget id="calculator">31.5 * 0.7</gadget>
<output>22.05</output>

<result>22.05</result>