3 pens and 3 notebooks cost a total of 25.2 yuan. 5.4 yuan per pen, how much is each notebook?
3支钢笔和3个笔记本共花了25.2元．每支钢笔5.4元，每个笔记本多少元？
<gadget id="calculator">25.2 / 3</gadget>
<output>8.4</output>

<gadget id="calculator">8.4 - 5.4</gadget>
<output>3</output>

<result>3</result>