A total of 890 pupils sat for the Social Studies mock exam. ¹₂ of the girls and ⁷₈ of the boys passed the mock exam. The same number of boys and girls failed the mock exam. How many more boys than girls passed the mock exam?
Fraction of the girls that failed the mock exam
= 1 - ¹₂
= ¹₂

Fraction of the boys that failed the mock exam
= 1 - ⁷₈
= ¹₈

Number of girls and boys that failed the mock exam is the same. Make the numerators the same.
¹₂ Girls = ¹₈ Boys

Total number of girls = 2 u
Total number of boys = 8 u

Total number of pupils
= 2 u + 8 u
= 10 u

10 u = 890

1 u = 890 ÷ 10 = 89

Number of girls that passed the mock exam = 1 u
Number of boys that passed the mock exam = 7 u

Number of more boys than girls who passed the mock exam
= 7 u - 1 u
= 6 u
= 6 x 89
= 534

Answer(s): 534