The ratio of the two acute angles of a right triangle is 2:1, what is the smallest angle in degrees?
一个直角三角形的两个锐角之比是2：1，最小的角是多少度．
<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">90 * (1/3)</gadget>
<output>30</output>

<result>30</result>