The ticket price of the park is 10 yuan per person. If you buy more than 30 tickets at one time, you will get a 20% discount. When the number of people is less than 30, at least how many people must go to the park. It is more cost-effective to buy 30 tickets.
公园票价每人10元，如果一次购票满30张，按八折优惠．请问当人数少于30人时，至少要有多少人去公园，买30张票反而合算．
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">30 / 10</gadget>
<output>3</output>

<gadget id="calculator">10 * (4/5) * 3</gadget>
<output>24</output>

<gadget id="calculator">24 + 1</gadget>
<output>25</output>

<result>25</result>