Hope Primary School originally planned to buy 12 toy balls at 1.5 yuan each. Now, 4.5 yuan is used out of the money to buy the balls to buy a skipping rope. How many balls can the remaining money buy?
希望小学原计划买12个玩具球，每个1.5元，现在从买此球的钱中拿出4.5元买了跳绳，剩下的钱可买几个皮球？
<gadget id="calculator">12 * 1.5</gadget>
<output>18</output>

<gadget id="calculator">18 - 4.5</gadget>
<output>13.5</output>

<gadget id="calculator">13.5 / 1.5</gadget>
<output>9</output>

<result>9</result>