Teacher Xu led 33 students to play in the park. The "signpost" at the ticket office reads: adult ticket: 8 yuan; child ticket: 4 yuan; for every 10 child tickets purchased, a child ticket will be given away. Please do the math, how much does it cost to buy tickets for this ride?
徐老师带领33名学生到公园去玩，购票处的"告示牌"上这样写到：成人票：8元；儿童票：4元；每购买10张儿童票赠送一张儿童票．请你算一算，这次游乐活动，要花多少钱买门票？
<gadget id="calculator">30 * 4</gadget>
<output>120</output>

<gadget id="calculator">120 + 8</gadget>
<output>128</output>

<result>128</result>