Question

In a group 2/5 of all students are girls and 2/3 of girls scored above 90% marks in
Mathematics. If 36 girls have scored above 90%, then select the option that indicates
the number of students who are not girls.
(1) 54
(2) 81
(3) 90
(4) 135​

Answer 1

Answer:

(2) 81

Step-by-step explanation:

Let the number of students in the group be x.

Total no. of girls = 2x/5

No. of girls who scored above 90% marks = 2/3 X 2x/5

                                                                 36 = 4x/15

                                                                    x = 135

Total no. of girls = 2x/5

                           = 54

No. of students who are not girls = 135-54

                                                       = 81