Xiao Wang looked out from the porthole of the plane and saw part of the island, part of the white clouds, and a small piece of sea area, if the white clouds occupy half of the window screen. It covers (1/4) of the island, so the island only takes up (1/4) on the window screen. Then, how much of the ocean is covered by the white cloud?
小王从飞机的舷窗向外看去，看见了部分海岛、部分白云，以及不大的一块海域，如果白云占窗口画面的一半．它遮住了岛的(1/4)，因此岛在窗口画面上只占(1/4)，那么，被白云遮住的那部分海洋占画面的多少．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">(1/4) / (3/4)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 - (1/2) - (1/4)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/3) - (1/4)</gadget>
<output>5/12 = around 0.416667</output>

<result>5/12 = around 0.416667</result>