Teacher Zhang brought 100 yuan, bought 4 footballs, and got back 16 yuan. How much is each football on average?
张老师带了100元钱，买了4个足球，找回16元钱，平均每个足球多少钱？
<gadget id="calculator">100 - 16</gadget>
<output>84</output>

<gadget id="calculator">84 / 3</gadget>
<output>28</output>

<result>28</result>