Marks obtained by 50 students from 100 are as follows

Find the probability that a student get marks:

(i) below 34, (ii) between 71-90

(iii) more than 70

(iv) less than or equal to (v) above 90.

The above chart shows the marks obtained by 50 students from total marks 100.

Total marks = 100

Total number of students = 50

Number of students scoring between 0-34 = 8

Number of students scoring between 35-50 = 9

Number of students scoring between 51-70 = 14

Number of students scoring between 71-90 = 11

Number of students scoring between 91-100 = 8

Now, Let the event that students getting marks below 34 be A.

Event that students getting marks between 71-90 be B.

Event that students getting marks more than 70 be C.

Event that students getting marks less than or equal to 50 be D.

Event that students getting marks above 90 be E.

Number of favourable outcomes of event A = 8

Number of favourable outcomes of event B = 11

Number of favourable outcomes of event C = 11 + 8 = 19

Number of favourable outcomes of event D = 8 + 9 = 17

Number of favourable outcomes of event E = 8

(i) Probability that a student get marks below 34 = Probability of occurrence of event A = P(A)

P(A) = = 0.16

(ii) Probability that a student get marks between 71-90 = Probability of occurrence of event B = P(B)

P(B) = = 0.22

(iii) Probability that a student get marks more than 70 = Probability of occurrence of event C = P(C)

P(C) = = 0.38

(iv) Probability that a student get marks less than or equal to 50 = Probability of occurrence of event D = P(D)

P(D) = = 0.34

(v) Probability that a student get marks above 90 = Probability of occurrence of event E = P(E)

P(E) = = 0.16