The truck transported 42 bags of rice and 58 bags of flour from the grain depot. Each bag of rice and flour weighed 45 kilograms. How many kilograms of grain did the truck transport from the grain depot in total?
卡车从粮库中运走42袋大米和58袋面粉，每袋大米和面粉的重量都是45千克，卡车一共从粮库中运走多少千克的粮食？
<gadget id="calculator">42 + 58</gadget>
<output>100</output>

<gadget id="calculator">45 * 100</gadget>
<output>4_500</output>

<result>4_500</result>