The ratio of the number of boys to that of girls in a school is 5 : 2. If 87% of the boys and 80% of the girls passed in the annual exams, then find the percentage of students who failed in the annual exams.
Answer & explanation
Correct answer: option 3
Given :-
Ratio of , Boys : Girls
5 : 2
Let Total number of boys = 50 & Total number of girls = 20
Passed boys students = 87%
So , Failed boys students = ( 100 - 87 )% = 13%
Number of boys failed = 50 × \(\frac{13}{100}\) = 6.5
Passed girls students = 80%
So , Failed girls students = ( 100 - 80 )% = 20%
Number of girls failed = 20 × \(\frac{20}{100}\) = 4
Number of failed students = ( 6.5 + 4) = 10.5
Total number of students = 50 + 20 = 70
Percentage of failed students = \(\frac{10.5}{70}\) × 100 = 15%
So , Number of failed students is 15%