The perimeter of an isosceles triangle is 28 cm, and the ratio of the base to the waist is 2:3. What is the length of the base of the triangle in cm?
等腰三角形的周长是28厘米，底边与腰的比是2：3，这个三角形的底边长多少厘米．
<gadget id="calculator">2 + 3 + 3</gadget>
<output>8</output>

<gadget id="calculator">2 / 8</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">28 * (1/4)</gadget>
<output>7</output>

<result>7</result>