There are two students, A and B. A has saved 27 yuan. After the two donate 15 yuan to the people in the disaster area, the ratio of the amount of money left by A and B is 3:4. B has savings how much?
有甲、乙两个同学，甲同学积蓄了27元钱，两人各为灾区人民捐款15元后，甲、乙两个同学剩下的钱的数量比是3：4，乙同学原来有积蓄多少元？
<gadget id="calculator">27 - 15</gadget>
<output>12</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">12 / (3/4)</gadget>
<output>16</output>

<gadget id="calculator">16 + 15</gadget>
<output>31</output>

<result>31</result>