Xiaoyang put the change given by her mother in the small box. Two months later, he used half of it to buy exercise books, and later deposited another 80.4 cents, and then used 8 cents less than half of it to buy extracurricular books, leaving 1.44 cents. How much money did you save before buying the exercise book?
小阳把妈妈给的零钱放在小盒里．两个月后用其中的一半买练习本，后来又存入8角4分，他又用其中比一半少8分的钱买了课外书，结果还剩1元4角4分．问未买练习本之前共存多少钱？
<gadget id="calculator">84 / 100</gadget>
<output>21/25 = around 0.84</output>

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

<gadget id="calculator">(21/25) * (1/2)</gadget>
<output>21/50 = around 0.42</output>

<gadget id="calculator">144 / 100</gadget>
<output>36/25 = around 1.44</output>

<gadget id="calculator">8 / 100</gadget>
<output>2/25 = around 0.08</output>

<gadget id="calculator">(36/25) - (21/25) - (2/25)</gadget>
<output>13/25 = around 0.52</output>

<gadget id="calculator">(21/50) + (13/25)</gadget>
<output>47/50 = around 0.94</output>

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

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

<gadget id="calculator">(47/50) / (1/4)</gadget>
<output>94/25 = around 3.76</output>

<result>94/25 = around 3.76</result>