One basketball is 12 yuan, and the price of three basketballs is equal to the price of one football. How much is the total cost of buying three basketballs and three footballs?
一个篮球12元，三个篮球的价格等于一个足球的价格，买三个篮球和三个足球共需多少元？
<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<gadget id="calculator">9 + 3</gadget>
<output>12</output>

<gadget id="calculator">12 * 12</gadget>
<output>144</output>

<result>144</result>