The table given below provides information about the marks obtained by a group of students in a test.
| Marks | No. of Students |
| Less than 10 | 2 |
| Less than 20 | 5 |
| Less than 30 | 6 |
| Less than 40 | 8 |
| Less than 50 | 10 |
What is total number of students in the group?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 10
Number of students who secure less than 10 marks = 2
Number of students who secure less than 20 marks = (5 - 2) = 3
Number of students who secure less than 30 marks = 6 - (3 + 2) = (6 - 5) = 1
Number of students who secure less than 40 marks = 8 - (2 + 3 + 1) = (8 - 6) = 2
Number of students who secure less than 50 marks = 10 - (2 + 3 + 1 + 2) = 2
Total number of students in the group = (2 + 3 + 1 + 2 + 2) = 10