Frequency related question

Durga prasad (Student CA CPT ) (116 Points)

07 June 2013  
Data given below refers to marks gained by a group of students
 
Class

Below 

10

Below

20

Below

30 

Below

40

Below

50
C.F

15

 

38

 

65

 

84

 

100

 

 

Find the no of students getting more than 30
marks.
a) 50 b) 53 c) 35 d) 52
 
Plz give your answer with explaination