There are 1800 students in a school, and 540 of them do not take part in sports activities. Of these students who do not take part, 5/9 are girls. There are 2/3 as many girls as boys in the school. How many boys take part in sports activities?

Total students = 1800

Number of students who did not take part = 540

Number of students who took part = 1800 - 540 = 1260

Number of students who did not take part = 540

Number of girls = 5/9 x 540 = 300

Number of boys = 540 - 300 = 240

2/3 as many girls as boys. ∴ ratio of girls to boys = 2:3

1800 : 5 = 360

Number of girls = 360 x 2 = 720

Number of boys = 360 x 3 = 1080

Number of boys who took part = 1080 - 240 = 840