Buy 5 bottles of mineral water and get 1 bottle free. If each of the 36 students wants to drink a bottle of mineral water, how many bottles do they need to spend at least.
矿泉水买5瓶送l瓶．36名同学每人要喝一瓶矿泉水，至少需要花钱买多少瓶．
<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<gadget id="calculator">36 / 6</gadget>
<output>6</output>

<gadget id="calculator">6 * 5</gadget>
<output>30</output>

<result>30</result>