Mr. Zhang won the lottery by purchasing a sports lottery. After paying personal income tax of 20% of the total prize money according to regulations, he got 200,000 yuan. How much is the total amount of prize money Mr. Zhang won this time?
张先生购买体彩中了奖，按规定交纳奖金总额20%的个人所得税后，得到了20万元．张先生这次中奖的奖金总额是多少万元？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">20 / (4/5)</gadget>
<output>25</output>

<result>25</result>