A total of 630 students sat for the Science exam. ⁵₆ of the boys and ⁸₉ of the girls failed the exam. The same number of girls and boys passed the exam. How many more girls than boys failed the exam?
Fraction of the boys that passed the exam
= 1 - ⁵₆
= ¹₆

Fraction of the girls that passed the exam
= 1 - ⁸₉
= ¹₉

Number of boys and girls that passed the exam is the same. Make the numerators the same.
¹₆ Boys = ¹₉ Girls

Total number of boys = 6 u
Total number of girls = 9 u

Total number of students
= 6 u + 9 u
= 15 u

15 u = 630

1 u = 630 ÷ 15 = 42

Number of boys that failed the exam = 5 u
Number of girls that failed the exam = 8 u

Number of more girls than boys who failed the exam
= 8 u - 5 u
= 3 u
= 3 x 42
= 126

Answer(s): 126