9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கற்கண்டு (இலக்கணம்) - தொடர் இலக்கணம், ஆகுபெயர் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -விரிவானம் (துணைப்பாடம்) - தாய்மைக்கு வறட்சி இல்லை! Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கவிதை பேழை (செய்யுள்) - மார்கழி பெருவிழா Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர்-இலக்கணம் - பகுபத உறுப்பிலக்கணம் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர் - இலக்கணம்-எழுத்து -அளபெடை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர்-துணைப்பாடம் - ஆறாம்திணை Important Questions And Answers Study Material - QB365 Set A

Published on: 09/12/2019
Probability
Download Tamil Nadu 9th Standard Maths question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Maths Test1.
In a recent year, of the 1184 centum scorers in various subjects in tenth standard public exams, 233 were in mathematics. 125 in social science and 106 in science. If one of the student is selected at random, find the probability of that selected student,
(i) is a centum scorer in Mathematics
(ii) is not a centum scorer in Science
2.
The probability that it will rain tomorrow is \(\\ \frac { 91 }{ 100 } \). What is the probability that it will not rain tomorrow?
3.
Team I and Team II play 10 cricket matches each of 20 overs. Their total scores in each match are tabulated in the table as follows:
| Match numbers | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Team I | 200 | 122 | 111 | 88 | 156 | 184 | 99 | 199 | 121 | 156 |
| Team II | 143 | 123 | 156 | 92 | 164 | 72 | 100 | 201 | 98 | 157 |
What is the relative frequency of Team I winning?
4.
In an office, where 42 staff members work, 7 staff members use cars, 20 staff members use two-wheelers and the remaining 15 staff members use cycles. Find the relative frequencies.
5.
When a dice is rolled, find the probability to get the number greater than 4?
6.
An urn contains 10 red and 8 white balls. One ball is drawn at random. Find the probability, that the ball drawn is white.
7.
One card is drawn from a pack of 52 cards, each of the 52 cards being equally likely to be drawn. Find the probability that the card drawn is
(i) an ace,
(ii) either red card or king.
8.
Tickets numbered from 1 to 20 are mixed up together and then a ticket is drawn at random. What is the probability that the ticket has a number which is a multiple of 3 or 7?
9.
What is the probability that a number selected from the numbers 1, 2, 3, ..., 25 is prime number when each of the given numbers is equally likely to be selected?
10.
Find the probability that a leap year selected at random will contain 53 Sundays.
11.
Two unbiased coins are tossed simultaneously find the probability of getting
(i) two heads
(ii) one head
(iii) at least one head
(iv) at most one head
12.
An unbiased die is thrown. What is the probability of getting
(i) an even number or a multiple of 3.
(ii) a number between 3 and 6.
13.
In a survey of 400 youngsters aged 16-20 years, it was found that 191 have their voter ID card. If a youngster is selected at random, find the probability that the youngster does not have their voter ID card.
14.
A company manufactures 10000 Laptops in 6 months. In that 25 of them are found to be defective. When you choose one Laptop from the manufactured, what is the probability that selected Laptop is a good one.
15.
When two coins are tossed, what is the probability that two heads are obtained?
16.
What is the probability of throwing an even number with a single standard dice of six faces?
17.
You are walking along a street. If you just choose a stranger crossing you, what is the probability that his next birthday will fall on a sunday?
18.
The six faces of the dice are called equally likely if the dice is _______.
Small
Fair
Six-faced
Round
19.
A collection of one or more outcomes of an experiment is called _______.
Event
Outcome
Sample point
None of the above
20.
A particular result of an experiment is called _______.
Trial
Simple event
Compound event
Outcome
21.
Which of the following cannot be taken as probability of an event?
0
0.5
1
-1
22.
If A is any event in S and its complement is A' then, P(A′) is equal to _______.
1
0
1-A
1-P(A)
23.
The probability of all possible outcomes of a random experiment is always equal to _______.
One
Zero
Infinity
Less than one
24.
A random experiment contains
Atleast one outcome
At least two outcomes
Atmost one outcome
Atmost two outcomes
25.
The probability of an event cannot be _______.
Equal to zero
Greater than zero
Equal to one
Less than zero
26.
The probability based on the concept of relative frequency theory is called _______.
Empirical probability
Classical probability
Both (1) and (2)
Neither (1) nor (2)
27.
Probability lies between _______.
−1 and +1
0 and 1
0 and n
0 and \(\infty \)
28.
A number between 0 and 1 that is used to measure uncertainty is called _______.
Random variable
Trial
Simple event
Probability
1.
Total number of centum scorers = 1184
Therefore n = 1184
(i) Let E1 be the event of getting a centum scorer in Mathematics.
Therefore n(E1) = 233, That is, r1 = 233
\(P({ E })_{ 1 }=\frac { { r }_{ 2 } }{ n } =\frac { 233 }{ 1184 } \)
(ii) Let E2 be the event of getting a centum scorer in Science.
Therefore n(E2 ) = 106, That is, r2 = 106
\(P({ E })_{ 2 }=\frac { { r }_{ 2 } }{ n } =\frac {106 }{ 1184 } \)
P(E'2) = 1− P(E2)
\(=1-\frac { 106 }{ 1184 } \)
\(=\frac { 1078 }{ 1184 } \)
2.
Let E be the event that it will rain tomorrow. Then E′ is the event that it will not rain tomorrow.
Since P(E) = 0.91, we have P(E′) = 1−0.91 (how?)
= 0.09
Therefore, the probability that it will not rain tomorrow
= 0.09
3.
In this experiment, each trial is a match where Team I faces Team II.
We are concerned about the winning status of Team I.
There are 10 trials in total; out of which Team I wins in the 1st, 6th and 9th matches.
The relative frequency of Team I winning the matches = \(\frac { 3 }{ 10 } \)or 0.3
4.
Total number of staff members = 42
The relative frequencies:
Car users \(=\frac { 7 }{ 42 } =\frac { 1 }{ 6 } \)
Two-wheeler users \(=\frac { 20 }{ 42 } =\frac { 10 }{ 21 } \)
Cycle users \(=\frac { 15 }{ 42 } =\frac { 5 }{ 14 } \)
5.
Sample space S = {1, 2, 3, 4, 5, 6}
Let E be the event of getting a number greater than 4
E = {5, 6}
\(P(E)=\frac { Number\ of\ favourable\ outcomes }{ Total\ number\ of\ outcomes } \)
\(P(E)=\frac { n(E) }{ n(S) } =\frac { 2 }{ 6 } =0.333...\)
6.

7.

8.
A= {3, 6, 9, 12, 15, 18, 7, 14}
P(A) = \(\frac { 8 }{ 20 } =\frac { 2 }{ 5 } \).
9.
A = {2, 3, 5, 7, 11, 13, 17, 19, 23}
P(A) = \(\frac{9}{25}\).
10.
S = {Sunday Monday, Monday Tuesday, Tuesday Wednesday, Wednesday Thursday, Thursday Friday, Friday Saturday, Saturday Sunday}
n(S) = 7; n (A) = 2; P(A) =\(\frac{2}{7}\).
11.
S = {HH, HT, TH, TT}
(i) probability of two heads = \(\frac { 1 }{ 4 } \)
(ii) probability of one head = \(\frac { 1 }{ 2 } \)
(iii) probability of at least one head = \(\frac { 3 }{ 4 } \)
(iv) probability of at most one head = \(\frac { 3 }{ 4 } \).
12.
Probability of getting an even number = \(\frac { 3 }{ 6 } =\frac { 1 }{ 2 } \)
Probability of getting a multiple of 3 =\(\frac { 2 }{ 6 } \)
Probability of getting an even multiple of 3 = \(\frac { 1 }{ 6 } \)
Probability of getting an even number or
a multiple of 3 = \(\frac { 1 }{ 2 } +\frac { 2 }{ 6 } -\frac { 1 }{ 6 } \)
=\(\frac { 3+2-1 }{ 6 } =\frac { 4 }{ 6 } =\frac { 2 }{ 3 } \)
(ii) Probability of a number between 3 and 6 =\(\frac { 2 }{ 6 } =\frac { 1 }{ 3 } \).
13.
No. of youngsters = 400
n(S)
No. of youngsters having voter id = 191
n(A)
No. of youngsters do not have their voter id
n(B) = 400 - 191 = 209
P(B) = \(\frac { n(B) }{ n(S) } =\frac { 209 }{ 400 } \).
14.
Total n(S) = 10,000
Defective n(A) = 25
Number of defective laptop is 25
Number of good laptop is = 10000 - 25 = 9975
Let A be the event of choosing a good laptop. n(A) = 9975
\(\mathrm{P}(\mathrm{A})=\frac{\mathrm{n}(\mathrm{A})}{\mathrm{n}(\mathrm{S})}=\frac{9975}{10000}\)
P(A) = 0.9975
Probability of getting a good laptop is 0.9975
15.
sample space when two coins are tossed (S) = {HH, TT, HT, TH}
n(S) = 4
Event of getting two heads (A) = {HH}
n(A) = 1
Probability of getting two heads p(A) = \(\frac { n(A) }{ n(S) } =\frac { 1 }{ 4 } \).
16.
Faces of a dice (S) = {1, 2, 3, 4,5, 6}
n(S) = 6
Event of throwing an even number
A = {2, 4, 6}, n(A) = 3
∴ Probability of throwing an even number
P(A) = \(\frac { n(A) }{ n(S) } =\frac { 3 }{ 6 } =\frac { 1 }{ 2 } \).
17.
(S) Days in a week = {Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday}
n(S) = 7
∴ No. of days in week = 7
(A) Event of selecting Sunday = {Sunday}
n(A) = 1
∴ Probability of selecting Sunday = \(\frac { n(A) }{ n(S) } =\frac { 1 }{ 7 } \).
18.
(b)
Fair
19.
(a)
Event
20.
(d)
Outcome
21.
(d)
-1
22.
(d)
1-P(A)
23.
(a)
One
24.
(b)
At least two outcomes
25.
(d)
Less than zero
26.
(a)
Empirical probability
27.
(b)
0 and 1
28.
(d)
Probability
9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - மணிமேகலை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - ஏறு தழுவுதல் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர் - தண்ணீர் Important Questions And Answers Study Material - QB365 Set A
Tamilnadu Stateboard 9th Standard Subjects
Tamilnadu Stateboard Standards