The school has a rectangular venue with a length of 40 meters and a width of 30 meters. In order to welcome the guests, it is necessary to arrange flowers around the venue, and put a tray every 5 meters. How many trays of flowers are needed?
学校有一个长方形的会场，长40米，宽30米，为了迎接来宾需绕会场一周摆放鲜花，每隔5米放一盘，需要多少盘鲜花？
<gadget id="calculator">40 * 2</gadget>
<output>80</output>

<gadget id="calculator">30 * 2</gadget>
<output>60</output>

<gadget id="calculator">80 + 60</gadget>
<output>140</output>

<gadget id="calculator">140 / 5</gadget>
<output>28</output>

<result>28</result>