Teacher Wang bought 3 pens and 20 notebooks and paid 105 yuan in total. It is known that the price of 5 notebooks is equal to that of one pen. How much is each notebook.
王老师买来3支钢笔和20本笔记本共付出105元，已知5本笔记本的价钱和一支钢笔相等，每本笔记本多少元．
<gadget id="calculator">15 * 3</gadget>
<output>45</output>

<gadget id="calculator">105 - 45</gadget>
<output>60</output>

<gadget id="calculator">60 / 20</gadget>
<output>3</output>

<result>3</result>