A basketball is 78 yuan, Mr. Zhang bought 3, if he brought 250 yuan, how much money is left?
一个篮球78元，张老师买了3个，如果他带了250元，还剩多少元？
<gadget id="calculator">78 * 3</gadget>
<output>234</output>

<gadget id="calculator">250 - 234</gadget>
<output>16</output>

<result>16</result>