Question
The percentages of marks obtained by a student in examination are given below:
|
Examination subjects |
% marks |
|
I |
58 |
|
11 |
64 |
|
III |
76 |
|
IV |
62 |
|
V |
85 |
Find the probability that the student gets
(i) a first class i.e. at least 60% marks
(ii) a distinction i.e. 75% or above
(ii) marks between 70% and 80%.
Solution
Total number of subjects = 5
(i) Number of subjects in which the student gets a first class = 4
∴ Probability that the students gets a first class 
(ii) Number of subjects in which the student gets a distinction = 2
∴ Probability that the student gets a distinction = 
(iii) Number of subjects in which the student gets marks between 70% and 80% = 2
∴ Probability that the students gets marks between 70% and 80% = 
