There are a total of 4,500 broiler chickens and laying hens in the chicken farm, of which broiler chickens accounted for (1/3). Later, a batch of small broiler chickens were bought back. At this time, the number of broiler chickens was equivalent to 40% of the total number. At this time, the company How many chickens are raised in the chicken farm?
养鸡场有肉鸡和蛋鸡共4500只，其中肉鸡只数占(1/3)，后来又买回一批小肉鸡，这时肉鸡只数相当于总只数的40%，此时这家养鸡场共养鸡多少只？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(2/3) / (3/5)</gadget>
<output>10/9 = around 1.111111</output>

<gadget id="calculator">4_500 * (10/9)</gadget>
<output>5_000</output>

<result>5_000</result>