There are 136 cows and 136 sheep in the farm. One cow eats an average of 65 kilograms of grass per week, and one sheep eats an average of 35 kilograms of grass every week. How many kilograms of grass should be prepared each week?
饲养场有136头牛和136只羊，1头牛每星期平均吃65千克草，1只羊每星期平均吃35千克草，每星期要准备多少千克草？
<gadget id="calculator">136 * 65</gadget>
<output>8_840</output>

<gadget id="calculator">136 * 35</gadget>
<output>4_760</output>

<gadget id="calculator">8_840 + 4_760</gadget>
<output>13_600</output>

<result>13_600</result>