If the perimeter of a rectangle is 24 cm and the ratio of the lengths of two adjacent sides is 3:1, what is the width of the rectangle in cm?
一个长方形的周长为24厘米，相邻两边长的比为3：1，那么这个长方形的宽为多少厘米．
<gadget id="calculator">24 / 2</gadget>
<output>12</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

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

<gadget id="calculator">12 * (1/4)</gadget>
<output>3</output>

<result>3</result>