One barrel of oil is used (5/8), and another 7 kg is added. At this time, the oil in the barrel is exactly (1/2) of this barrel. How many kilograms is this barrel of oil in total?
一桶油用去(5/8)，又加进7千克，这时桶里的油正好是这桶油的(1/2)．这桶油一共有多少千克？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">5 / 8</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">1 - (5/8)</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">(1/2) - (3/8)</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">7 / (1/8)</gadget>
<output>56</output>

<result>56</result>