Among the three interior angles of a right triangle, the measure of the smallest angle is (1/5) of the largest angle. What is the smallest angle?
在一个直角三角形的三个内角中，最小的角的度数是最大角度数的(1/5)，这个最小的角是多少度．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">90 * (1/5)</gadget>
<output>18</output>

<result>18</result>