A notebook costs 2 yuan and 50 cents, how much does it cost to buy 8 notebooks?
一本笔记本2元5角，买8本要多少元．
<gadget id="calculator">5 / 10</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 + (1/2)</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">(5/2) * 8</gadget>
<output>20</output>

<result>20</result>