Question

On a school trip the ratio of the number of teachers to students is 1:15. the ratio of the number of male students to female students is 7:5. work out percentage of all female students

1. The Percentage of female students in the school trip is 39%.
According to the statement
we have given that the some ratio of the class students and teachers and we have to find the percentage of female students on the school trip.
So, For this purpose,
The Given information is:
The ratio of the number of teachers to the number of students is 1:15.
and the ratio of the number of male and female students is 7:5
Suppose the number of teachers is x. So, students become 15x
For the ratio of male to female, assume male is 7y, so female is 5y
The sum of the male and female students comprises the whole student community is:
15x = 7y + 5y
15x = 12y
5x = 4y
then
The percentage of female students on the trip is calculated by use the below written formula. So,
Percentage of female students = (5y / x +15x) * 100
Percentage of female students = (5y /16x) * 100
Substitute the value of y which is y = 5/4x
So,
Percentage of female students = (5*5/4x / 16x) * 100
Percentage of female students = 625/16
Percentage of female students = 39%.
So, The Percentage of female students in the school trip is 39%.