There are 1,600 students in the fourth, fifth, and sixth grades of Shengli Primary School, 740 students in the sixth grade, and 370 students in the fifth grade. How many students are there in the fourth grade of Shengli Primary School?
胜利小学四、五、六年级共有学生1600人，六年级有学生740人，五年级有学生370人，求胜利小学四年级有学生多少人？
<gadget id="calculator">1_600 - 740 - 370</gadget>
<output>490</output>

<result>490</result>