The original price of a pen is 30 yuan, and now it is sold at a 20% discount. How much is the current price?
一支钢笔原价30元，现在打8折出售，现在售价为多少元．
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">30 * (4/5)</gadget>
<output>24</output>

<result>24</result>