The ratio of the three angles of a triangle is 2:4:3, what is the largest angle?
三角形三个角度数的比是2：4：3，最大的角是多少．
<gadget id="calculator">2 + 4 + 3</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">180 * (4/9)</gadget>
<output>80</output>

<result>80</result>