The ratio of the number of points cards between Eddie and Weier is 4:5. If Eddie gives Weier 5 cards, then the number of point cards between the two becomes 1:2. How many point cards does Eddie have?
艾迪和薇儿原有积分卡的数量之比为4：5．若艾迪给微儿5张，那么两人的积分卡数量变为1：2，求艾迪原来有多少张积分卡？
<gadget id="calculator">4 + 5</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(4/9) - (1/3)</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">5 / (1/9)</gadget>
<output>45</output>

<gadget id="calculator">45 * (4/9)</gadget>
<output>20</output>

<result>20</result>