Xiao Ming and Xiao Hua go to buy the same exercise book, Xiao Ming buys 7 books, Xiao Hua buys 5 books, Xiao Ming spends 6 cents more than Xiao Hua, how much is each exercise book of this kind.
小明和小华去买同样的练习本，小明买7本，小华买5本，小明用的钱比小华多6角钱，这种练习本每本是多少钱．
<gadget id="calculator">7 - 5</gadget>
<output>2</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<result>3</result>