Red Star Sporting Goods Monopoly is running a promotional event, buy five get one free, each volleyball costs 45 yuan, how much does it cost to buy 30 such volleyballs?
红星体育用品专卖搞促销活动，买五送一，每个排球要45元，买这样的排球30个，共需要多少钱？
<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">45 * (5/6)</gadget>
<output>75/2 = around 37.5</output>

<gadget id="calculator">30 * (75/2)</gadget>
<output>1_125</output>

<result>1_125</result>