RD SHARMA Solutions for Class 9 Maths Chapter 25 - Probability

Page / Exercise

Chapter 25 - Probability Exercise Ex. 25.1

Question 1
A coin is tossed 1000 times with the following frequencies:

Head : 455, Tail : 545

Compute the probability for each event.
Solution 1
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 2

Two coins are tossed simultaneously 500 times with the following frequencies of different outcomes:

Two heads : 95 times

One tail : 290 times

No head : 115 times

Find the probability of occurrence of each of these events.

Solution 2

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 3
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 3
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 4
1500 families with 2 children were selected randomly and the following data were recorded:

Number of girls in a family: 0 1 2
Number of families: 211 814 475


If a family is chosen at random, compute the probability that it has:

(i) No girl

(ii) 1 girl

(iii) 2 girls

(iv) at most one girl

(v) more girls than boys
Solution 4
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 5
In a cricket match, a batsman hits a boundary 6 times out of 30 balls he plays.

Find the probability that on a ball played:

(i) he hits boundary

(ii) he does not hit a boundary.
Solution 5
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 6
The percentage of marks obtained by a student in monthly unit tests are given below:

Units Test: I II III IV V
Percentage of marks obtained: 69 71 73 68 76


Find the probability that the student gets:

(i) More than 70% marks

(ii) less than 70% marks

(iii) a distinction.
Solution 6
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 7
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 7
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 8
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 8
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 9
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 9
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 10

 

Following table shows the birth month of 40 students of class IX.

Jan

Feb

March

April

May

June

July

Aug.

Sept.

Oct.

Nov.

Dec.

3

4

2

2

5

1

2

5

3

4

4

4

Find the probability that a student was born in August.

  

Solution 10

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 11
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 11
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 12
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 12
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 13
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 13
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Question 14
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability
Solution 14
Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Chapter 25 - Probability Exercise 25.16

Question 1

The probability of an impossible event is

(a) 1

(b) 0

(c) less than 0

(d) greater than 1

Solution 1

The probability of an impossible event is always zero since the chances of occurring of that event is zero.

Hence, correct option is (b).

Question 2

The probability of a certain event is

(a) 0

(b) 1

(c) greater than 1

(d) less than 0

Solution 2

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 3

The probability an event of a trial is

(a) 1

(b) 0

(c) less than 1

(d) more than 1

Solution 3

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 4

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Solution 4

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 5

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Solution 5

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Chapter 25 - Probability Exercise 25.17

Question 6

A coin is tossed 1000 times, if the probability of getting a tail is 3/8, how many times head is obtained?

(a) 525

(b) 375

(c) 625

(d) 725

Solution 6

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 7

A dice is rolled 600 times and the occurrence of the outcomes 1, 2, 3, 4, 5 and 6 are given below:

Outcome 1 2 3 4 5 6
frequency 200 30 120 100 50 100

The probability of getting a prime number is

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Solution 7

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 8

The percentage of attendance of different classes in a year in a school is given below:

Class: X IX VIII VII VI V
Attendance: 30 62 85 92 76 55

What is the probability that the class attendance is more than 75%?

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Solution 8

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 9

A bag contains 50 coins and each coin is marked from 51 to 100. One coin is picked at random. The probability that the number on the coin is not a prime number, is

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Solution 9

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Question 10

In a football match, Ronaldo makes 4 goals from 10 penalty kicks. The probability of converting a penalty kick into a goal by Ronaldo, is

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability

Solution 10

Rd-sharma Solutions Cbse Class 9 Mathematics Chapter - Probability