There are 4 kilograms of oil in a bucket, if (3/4) of the oil is poured out for the first time, and (3/4) kilograms are poured out for the second time, how many kilograms of oil are left in the bucket.
一个桶里有油4千克，第一次倒出油的(3/4)，第二次倒出(3/4)千克，桶内还剩油多少千克．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 - (3/4)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">4 * (1/4)</gadget>
<output>1</output>

<result>1/4 = around 0.25</result>