There are 126 roosters, the number of hens is 6 times that of roosters, and the number of ducks is 45 less than the total number of roosters and hens. How many ducks are there? (I will do it in two ways, I will do it in two ways)
有公鸡126只，母鸡的只数是公鸡的6倍，鸭的只数比公鸡和母鸡的总只数少45只，鸭有多少只？(会用两种方法做，就用两种方法做)
<gadget id="calculator">126 * 6</gadget>
<output>756</output>

<gadget id="calculator">756 - 45</gadget>
<output>711</output>

<gadget id="calculator">126 + 711</gadget>
<output>837</output>

<result>837</result>