Probability Model Question Paper

9th Standard

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Maths

Time : 01:30:00 Hrs
Total Marks : 40
8 x 1 = 8
1. A number between 0 and 1 that is used to measure uncertainty is called

(a)

Random variable

(b)

Trial

(c)

Simple event

(d)

Probability

2. The probability of an event cannot be

(a)

Equal to zero

(b)

Greater than zero

(c)

Equal to one

(d)

Less than zero

3. The probability of all possible outcomes of a random experiment is always equal to

(a)

One

(b)

Zero

(c)

Infinity

(d)

All of the above

4. If A is any event in S then its complement P(A′) is equal to

(a)

1

(b)

0

(c)

1-A

(d)

1-P(A)

5. Which of the following cannot be taken as probability of an event?

(a)

0

(b)

0.5

(c)

1

(d)

-1

6. A collection of one or more outcomes of an experiment is called

(a)

Event

(b)

Outcome

(c)

Sample point

(d)

None of the above

7. The six faces of the dice are called equally likely if the dice is

(a)

Small

(b)

Fair

(c)

Six-faced

(d)

Round

8. A letter is chosen at random from the word “STATISTICS”. The probability of getting a vowel is

(a)

$\frac { 1 }{ 10 }$

(b)

$\frac { 2 }{ 10 }$

(c)

$\frac { 3 }{ 10 }$

(d)

$\frac { 4 }{ 10 }$

9. 10 x 2 = 20
10. What is the probability of drawing a King or a Queen or a Jack from a deck of cards?

11. There are 24 balls in a pot. If 3 of them are Red, 5 of them are Blue and the remaining are Green then, what is the probability of picking out (i) a Blue ball, (ii) a Red ball and (iii) a Green ball?

12. When two coins are tossed, what is the probability that two heads are obtained?

13. In a football match, a goalkeeper of a team can stop the goal, 32 times out of 40 attempts tried by a team. Find the probability that the opponent team can convert the attempt into a goal.

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. The probability of guessing the correct answer to a certain question is $\frac { x }{ 3 }$. If the probability of not guessing the correct answer is $\frac { x }{ 5 }$, then find the value of x.

16. 1500 families were surveyed and following data was recorded about their maids at homes

 Type of maids Only part time Only full time Both Number of families 860 370 250

A family is selected at random. Find the probability that the family selected has
(i) Both types of maids
(ii) Part time maids
(iii) No maids

17. 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?

18. A bag contains 3 red and 2 blue marbles. A marble is drawn at random. What is the probability of drawing a blue marble?

19. An urn contains 10 red and 8 white balls. One ball is drawn at random. Find the probability, that the ball drawn is white.

20. 4 x 3 = 12
21. When a dice is rolled, find the probability to get the number greater than 4?

22. 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?

23. The probability that it will rain tomorrow is $\\ \frac { 91 }{ 100 }$. What is the probability that it will not rain tomorrow?

24. 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