A desk (18 yuan) and a chair (42 yuan) are a set. The experimental primary school plans to buy 45 sets of such desks and chairs. How much will it cost in total?
一张课桌(18元)和一把椅子(42元)是一套，实验小学准备买45套这样的课桌椅，一共要花多少钱？
<gadget id="calculator">18 + 42</gadget>
<output>60</output>

<gadget id="calculator">60 * 45</gadget>
<output>2_700</output>

<result>2_700</result>