A barrel of oil weighs 124.8 kg in total. After half of the oil is used, the barrel weighs 67.4 kg. How many kilograms of original oil?
1桶油连桶共重124.8千克．油用去一半后，连桶重67.4千克．原有油多少千克？
<gadget id="calculator">124.8 - 67.4</gadget>
<output>57.4</output>

<gadget id="calculator">57.4 * 2</gadget>
<output>114.8</output>

<result>114.8</result>