Question 895510
Total students = X

No. of boys = {{{1,800 = X*5/9}}}

{{{X = 360*9 = 3240}}}

No. of girls = 3240 - 1800 = 1440

Girls : Boys = 1440 : 1800

144 : 180 ===> 72 : 90 ====> 36 : 45

Answer {{{4 : 5}}}