It is known that the sum of the interior angles of a triangle is 180°, and the degree ratio of the three angles is 1:2:3, then what is the largest angle in degrees.
已知三角形的内角和为180°，且三个角的度数比为1：2：3，那么最大的角是多少度．
<gadget id="calculator">1 + 2 + 3</gadget>
<output>6</output>

<gadget id="calculator">3 / 6</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">180 * (1/2)</gadget>
<output>90</output>

<result>90</result>