During the promotion period on New Year's Day, Aunt Li bought an LCD TV with an original price of 4,000 yuan at a 15% discount. How much does Aunt Li have to pay?
元旦促销期间，李阿姨用八五折买了一台原价为4000元的液晶电视，李阿姨要付多少元．
<gadget id="calculator">85 / 100</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">4_000 * (17/20)</gadget>
<output>3_400</output>

<result>3_400</result>