The ratio of the perimeters of two squares A and B is 5:2. The perimeter of square A is 30 meters. What is the area of square B in square meters?
甲、乙两个正方形的周长的比是5：2，甲正方形的周长是30米，乙正方形的面积是多少平方米．
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">30 * (2/5)</gadget>
<output>12</output>

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

<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<result>9</result>