Mr. Zhang bought a pen and a book in a stationery store. The unit price of a pen is 15.8 yuan, which is 1.2 yuan less than the unit price of a book. How much did Mr. Zhang share?
张老师在文具店里买了一支钢笔和一本书，一支钢笔的单价15.8元，比一本书的单价少1.2元，张老师一共用了多少元？
<gadget id="calculator">15.8 + 1.2 + 15.8</gadget>
<output>32.8</output>

<result>32.8</result>