Question

The ratio of boys and girls in a class is 5:3. If there are 120 students in the class, then the number of boys is​

Answer 1

Step-by-step explanation:

let g=girls

b=boys

the ratio is 5:3=5/3

b/g=5/3

cross mltiply

b=g(5/3)------eq 1

b + g = 120-----eq 2

solve g and b substitution

substitute eq 1-eq 2

g(5/3)+g=120

getting common denominator to add directly

(5g+3g)/3=120

cross multiply

8g=360

then divide it by 8

8g/8=360/8

g=45--------------------girls number

for boys

use eq -1

b=g(5/3)

b=45(5/3)

b=75---------boys number

checking

student number=120

75+45=120-----