The price of 9 pens is the same as that of 3 schoolbags. It costs 126 yuan to buy 6 pens. What is the price of each schoolbag?
9支钢笔和3个书包的价钱相等，买六支钢笔要126元，每个书包的价钱是多少？
<gadget id="calculator">126 / 6</gadget>
<output>21</output>

<gadget id="calculator">9 / 3</gadget>
<output>3</output>

<gadget id="calculator">21 * 3</gadget>
<output>63</output>

<result>63</result>