Mother gave Liangliang a certain amount of money to go to the vegetable market to buy vegetables. Liangliang used 25% of the money to buy fish, 30 yuan to buy meat, and the remaining 15% to buy vegetables. How much money did mother prepare for Liangliang?
妈妈给了一定数额的钱让亮亮去菜市场买菜，亮亮用25%的钱买了鱼，又用30元买了肉，剩下15%的钱买蔬菜．妈妈为亮亮准备了多少钱？
<gadget id="calculator">15 / 100</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (3/20) - (1/4)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">30 / (3/5)</gadget>
<output>50</output>

<result>50</result>