On December 25th, Xiaoming celebrated his birthday. His father gave him a fast-growing tree. His father told Xiaoming that this tree could grow 50% of its original height every day. On the evening of December 27th, Xiaoming measured the height of the fast-growing tree. It is 22.5 centimeters, then, on the night of December 25, how many centimeters is the height of the fast-growing tree?
12月25日，小明过生日，爸爸送给他一棵速生树，爸爸告诉小明，这棵树，每天可以长高原来高度的50%，12月27日晚上，小明测量了一下速生树的高度是22.5厘米，那么，12月25日晚上，速生树高多少厘米．
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 + (1/2)</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">(3/2) * (3/2)</gadget>
<output>9/4 = around 2.25</output>

<gadget id="calculator">22.5 / (9/4)</gadget>
<output>10</output>

<result>10</result>