Q. Marks obtained by all the students of class 12 are presented in a frequency distribution with classes of equal width. Let the median of this grouped data be 14 with median class interval 12-18 and median class frequency 12. If the number of students whose marks are less than 12 is 18, then the total number of students is
A) 52
B) 48
C) 44
D) 40
Explanation
[Solution by Dr. Abubacker] Median $=l+\frac{N/2-F}{f}\,h$: $14=12+\frac{N/2-18}{12}\cdot6\Rightarrow N/2-18=4$, so $N=44$. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.