Xinhua Bookstore is going to sell a set of books priced at 80 yuan at 64 yuan. How much can you save by buying a set of this book?
新华书店准备将一套定价为80元的图书以64元卖出．要买一套这种图书，可以节省多少．
<gadget id="calculator">80 - 64</gadget>
<output>16</output>

<gadget id="calculator">16 / 80</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>