In an isosceles triangle, the ratio of the base angle to the apex angle is 1:2, what is the base angle in degrees?
一个等腰三角形，底角与顶角度数的比是1：2，底角是多少°度．
<gadget id="calculator">1 + 1 + 2</gadget>
<output>4</output>

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

<gadget id="calculator">180 * (1/4)</gadget>
<output>45</output>

<result>45</result>