The four numbers (1/2), x, y, (3/4) are arranged in ascending order, if the difference between two adjacent numbers is the same, then y=how much.
四个数(1/2)，x，y，(3/4)是由小到大排列的，如果相邻两数之间的差都相同，则y=多少．
<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(3/4) - (1/12)</gadget>
<output>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>