Share

There Are 36 Members in a Student Council in a School and the Ratio of the Number of Boys to the Number of Girls is 3: 1. How Any More Girls Should Be Added to the Council So that the Ratio of the Number of Boys to the Number of Girls May Be 9: 5? - ICSE Class 10 - Mathematics

Question

There are 36 members in a student council in a school and the ratio of the number of boys to the number of girls is 3: 1. How any more girls should be added to the council so that the ratio of the number of boys to the number of girls maybe 9: 5?

Solution

A ratio of number of boys to the number of girls = 3: 1
Let the number of boys be 3x and the number of girls be x.
3x + x = 36
4x = 36
x = 9
∴ Number of boys = 27
Number of girls = 9
Le n number of girls be added to the council.
From given information, we have:

27/(9 + n) = 9/5

135 = 81 + 9n

9n = 54

n = 6

Thus 6 girl are added to the council

Is there an error in this question or solution?

APPEARS IN

Selina Solution for Selina ICSE Concise Mathematics for Class 10 (2018-2019) (2017 to Current)
Chapter 7: Ratio and Proportion (Including Properties and Uses)
Ex.7D | Q: 18

Video TutorialsVIEW ALL 

Solution There Are 36 Members in a Student Council in a School and the Ratio of the Number of Boys to the Number of Girls is 3: 1. How Any More Girls Should Be Added to the Council So that the Ratio of the Number of Boys to the Number of Girls May Be 9: 5? Concept: Ratios.
S