A trapezoidal lawn measures 76m at the top, 84m at the bottom, and 45m in height. If the cost per square meter is 15 yuan, how much will it cost to repair the lawn?
一块梯形草坪，量得上底76m，下底84m，高45m，如果每平方米的造价是15元，修这块草坪共需要多少元？
<gadget id="calculator">76 + 84</gadget>
<output>160</output>

<gadget id="calculator">45 / 2</gadget>
<output>45/2 = around 22.5</output>

<gadget id="calculator">160 * (45/2)</gadget>
<output>3_600</output>

<gadget id="calculator">15 * 3_600</gadget>
<output>54_000</output>

<result>54_000</result>