Xiaohua bought 5 pens and 12 exercise books, which cost a total of 38.6 yuan. 5.8 yuan per pen, how much is each exercise book? (Solve first with equations, then with arithmetic)
小华买了5枝钢笔和12个练习本，共花去38.6元．每枝钢笔5.8元，每个练习本多少钱？(先用方程解，再用算术方法解)
<gadget id="calculator">5.8 * 5</gadget>
<output>29</output>

<gadget id="calculator">38.6 - 29</gadget>
<output>9.6</output>

<gadget id="calculator">9.6 / 12</gadget>
<output>0.8</output>

<result>0.8</result>