Question

The ratio of boys and girls in any class is 11:13. If 8 girls and 4 boys join the class , the ratio becomes 4:5. Find the number of students in the class- (ANSWER WITH SOLUTION)

a)108

b)120

c)96

d)240


Plz answer

Answer 1

let the no. of boys be 11x and girls be 13x ,so their ratio is 11:13.
now 8 girls and 4 boys joined in ..so
11x+4 is now new no. of boys
and 13x+8 is new no. of girls
a/q
11x+4/13x+8 =4/5
so,55x+20=52x+32
so, 3x=12
so, x=4
hence no. of boys and girls will be 44 and 52.
total=96.
new no. will be 48 and 60....so total =108

thanks ..mark it as brainliest !!

Answer 2

boys in the class = 11x
girls in the class = 13x

when the new students came:

boys = 11x + 4
girls = 13x + 8

now the ratio is :
(11x + 4)/(13x + 8) = 4/3

by cross multiplying:

52x +32 = 55x + 20
by solving:

12 = 3x
x = 4

now,
boys = 11x + 4
        = 44+4
        =48
girls = 13x + 8
         = 52 + 8
         = 60

Total students = 48 + 60
                        = 108