Li Jiang bought 2 pencils and 6 exercise books for a total of 4.20 yuan, 0.60 yuan for each pencil, how much is each exercise book?
李江买2支铅笔和6本练习本一共用了4.20元，每支铅笔0.60元，每本练习本多少元？
<gadget id="calculator">0.6 * 2</gadget>
<output>1.2</output>

<gadget id="calculator">4.2 - 1.2</gadget>
<output>3</output>

<gadget id="calculator">3 / 6</gadget>
<output>1/2 = around 0.5</output>

<result>1/2 = around 0.5</result>