In the second quarter, an average of 4 tons of coal was burned per day. How many tons of coal were burned in the second quarter?
第二季度平均每天烧煤4吨，第二季度一共烧煤多少吨？
<gadget id="calculator">30 + 31 + 30</gadget>
<output>91</output>

<gadget id="calculator">4 * 91</gadget>
<output>364</output>

<result>364</result>