A barrel of oil, 2/3 of it is used up, exactly 50 kilograms, how many kilograms is this barrel of oil?
一桶油，用去了它的(2/3)，正好用去50千克，这桶油有多少千克？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">50 / (2/3)</gadget>
<output>75</output>

<result>75</result>