Each exercise book is 0.8 yuan, and Xiao Ming bought several copies with 10 yuan, and got back 4.4 yuan. Q: How many exercise books did Xiao Ming buy?
练习本每本0.8元，小明拿10元买了若干本，还找回4.4元．问：小明买了几本练习本？
<gadget id="calculator">10 - 4.4</gadget>
<output>5.6</output>

<gadget id="calculator">5.6 / 0.8</gadget>
<output>7</output>

<result>7</result>