A school has 450 students in the first, second and third grades, and the ratio of students in the three grades is 2:3:4. Ask how many students are in the grade with the largest number of students.
一所学校一、二、三年级学生总人数450人，三个年级的学生比例为2：3：4，问学生人数最多的年级有多少人．
<gadget id="calculator">2 + 3 + 4</gadget>
<output>9</output>

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

<gadget id="calculator">450 * (4/9)</gadget>
<output>200</output>

<result>200</result>