The wholesale price of a barrel of mineral water is 3 yuan, and the retail price is 5 yuan. Today, Xiao Ming's store earned 60 yuan. How many barrels of mineral water did Xiao Ming sell today?
一桶矿泉水批发价是3元，零售价是5元，今天小明的商店赚了60元．小明今天卖出了多少桶矿泉水．
<gadget id="calculator">5 - 3</gadget>
<output>2</output>

<gadget id="calculator">60 / 2</gadget>
<output>30</output>

<result>30</result>