There are 2,700 hens in the farm, and the number of hens is 7.5 times more than that of roosters, which is 450. How many roosters are there in the farm?
饲养场养了母鸡2700只，母鸡的只数比公鸡的7.5倍还多450只，饲养场有公鸡多少只？
<gadget id="calculator">2_700 - 450</gadget>
<output>2_250</output>

<gadget id="calculator">2_250 / 7.5</gadget>
<output>300</output>

<result>300</result>