A barrel of oil with barrels weighs 157.8 kilograms, and after half of the oil is used, the barrels still weigh 82.8 kilograms. How many kilograms of oil is in this barrel?
一桶油连桶重157.8千克，用去一半后油后，连桶还重82.8千克．这桶油有油多少千克．
<gadget id="calculator">157.8 - 82.8</gadget>
<output>75</output>

<gadget id="calculator">75 * 2</gadget>
<output>150</output>

<result>150</result>