In an examination, the percentage of students qualified to the number of students appeared from school A is 70\%. In school B, the number of students appeared is 20\% more than the students appeared from school A and the number of students qualified from school B is 50\% more than the students qualified from school A. What is the percentage of students qualified to the number of students appeared from school B?
(a)30\%
(b)70\%
(c)78.5\%
(d)87.5\%
Answer
Answer (as printed): D
Explanation
Let number of students appeared from school $A=100$. Then, number of students qualified from school $A=70$. Number of students appeared from school $B=120$. Number of students qualified from school $B$ $$=\left(\frac{150}{100} \times 70\right)=105 .$$ ∴ $\quad$ Required percentage $=\left(\frac{105}{120} \times 100\right) \%=87.5 \%$.
Explanation as extracted from the printed page; notation may be imperfect.