The table given below shows the marks obtained by 80 students of a class in a test with maximum marks 100 .

A student of the class is selected at random .
Find the probability that he gets
(i) less than `15%` marks ,
(ii) `60` or more marks and
(iii) less than `45` marks .

Options

A. `(3)/(40)`, `(1)/(4)`, `(9)/(20)`
B. `(7)/(40)`, `(3)/(4)`, `(3)/(20)`
C. `(9)/(40)`, `(3)/(4)`, `(11)/(20)`
D. `(17)/(40)`, `(1)/(4)`, `(17)/(20)`

Answer

A

Explanation

Total number of students = 80 .
(i) P(The student gets less than 15% marks)
= `("number of students getting less than 15 marks")/("total number of students")`
`= (6)/(80) = (3)/(40)` .
(ii) P(The student gets 60 or more marks)
`= ("number of students getting 60 or more marks")/("total number of students")`
= `(16 + 4)/(80) = (20)/(80) = (1)/(4)` .
(iii) P(The student gets less than 45 marks )
= `("number of students getting less than 45 marks")/("total number of students")`
`= (6 + 13 + 17)/(80) = (36)/(80)= (9)/(20)` .