Junjun bought 8 exercise books, and Huahua bought 5 of the same exercise books. Junjun spent 1 yuan and 8 cents more than Huahua. How much is each exercise book?
军军买了8本练习本，华华买了5本同样的练习本，军军比华华多用了1元8角，问每本练习本多少钱？
<gadget id="calculator">8 / 10</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 + (4/5)</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">8 - 5</gadget>
<output>3</output>

<gadget id="calculator">(9/5) / 3</gadget>
<output>3/5 = around 0.6</output>

<result>3/5 = around 0.6</result>