The cafeteria burns 300 kg of coal in September, and saves 40 kg of coal in October compared with September. How many kilograms of coal are burned in two months?
食堂九月份烧煤300千克，十月分比九月份节约用煤40千克．两个月共烧煤多少千克？
<gadget id="calculator">300 - 40</gadget>
<output>260</output>

<gadget id="calculator">260 + 300</gadget>
<output>560</output>

<result>560</result>