Elementary Event

Q.

An event with only 1 outcome is called __.

1. a complementary event

2. an equally likely event

3. an elementary event

4. a single event

Q.

An event, having only one favourable outcome, is called:

1. an impossible event

2. an elementary event

3. a sure event

4. none of the above

Q. A bag contains 5 red, 4 blue and 3 green balls. One ball is drawn at random. Find the probability that the ball drawn is
i) blue
ii) not red
iii) either red or green
iv) black
[4 MARKS]

Q.

A dice is thrown twice. The probability of getting 4, 5 or 6 in the first and 1, 2, 3 or 4 in the second throw is

1. $\frac{1}{3}$

2. $\frac{2}{3}$

3. $\frac{1}{2}$

4. $\frac{1}{4}$

Q.

Three balls are to be picked from a bag containing 6 black, 5 white and 4 red balls. What is the probability that all the three balls are of different colour?

1. $\frac{25}{91}$

2. $\frac{22}{91}$

3. $\frac{24}{91}$

4. $\frac{26}{91}$

Q.

A die is thrown once, the probability of getting an even prime number is___

1. $\frac{1}{6}$

2. $\frac{1}{2}$

3. $\frac{1}{3}$

4. $\frac{2}{6}$

Q.

A bag contains red, blue and green balls. It is twice as likely to pick a blue ball as compared to a red ball, and it is thrice as likely to pick a green ball as compared to a red ball. What is the probability of picking a green ball? [3 MARKS]

Q.

A bag contains 5 red , 4 green and 3 blue balls. If a ball is drawn at random, what is the probability of getting a red ball

1. $\frac{5}{12}$

2. $\frac{1}{3}$

3. $\frac{1}{4}$

4. 1

Q. A bag contains 5 black, 4 green and 6 red balls. If a ball is drawn at random from the bag, find the probability that it will be:
i) red
ii) black
iii) green
[3 MARKS]

Q. Two dice are thrown together. The probability that sum of the two numbers will be 2 is:

1. $\frac{1}{2}$
2. $\frac{1}{36}$
3. $\frac{1}{4}$
4. $\frac{1}{8}$

Q.

The probability of drawing a blue ball from a bag that contains 3 white balls, 8 blue balls and 5 red balls is

1. P <= 0.25

2. P < 0.5

3. P = 0.5

4. P > 0.5

Q.

Two dice are thrown at the same time. Find the probability of getting the same number on both dice.

1. 1/3

2. 2/5

3. 1/6

4. 5/6

Q.

One ball is selected at random from a bag containing $12$ balls of which $p$ are white. When further $6$ white balls are added, the probability of selecting a white ball is doubled. Find $p$.

Q.

A bag contains red, blue and green balls. It is twice as likely to pick a blue ball as compared to a red ball, and it is thrice as likely to pick a green ball as compared to a red ball. What is the probability of picking a green ball?

Q. Question 21(ii)
Two dice are thrown together. Find the probability that the product of the numbers on the top of the dice is 12?

Q.

An event with only 1 outcome is called __.

1. a complementary event

2. a single event

3. an elementary event

4. an equally likely event

Q.

What is the probability of getting a sum of 7 on a roll of two dice?

1. 7/12

2. 1/11

3. 1/6

4. 2/3

Q.

A purse contains $4$ copper and $3$ silver coins. Another purse contains $6$ copper and $2$ silver coins. A coin is taken out from any purse, the probability that it is a silver coin, is

1. $\frac{37}{56}$

2. $\frac{19}{56}$

3. $\frac{4}{7}$

4. $\frac{2}{3}$

Q. Question 5
A jar contains 24 marbles, some are green and others are blue. If a marble is drawn at random from the jar, the probability that it is green is $\frac{2}{3}$.
Find the number of blue balls in the jar.

Q.

Find the probability of getting an even sum when you toss two dice simultaneously.

Q. A die thrown once. What is the probability of getting a number lying between 2 and 6?

Q. A jar contains 24 marbles, some are green and others are blue. If a marble is drawn at random from the jar, the probability that it is green is $\frac{2}{3}$.
Find the number of blue balls in the jar.

Q.

The probability of picking the letter K if you pick a random letter from the word TREKKING is $\frac{x}{4}$. x is

___

Q.

State whether the given statement is true or false:

The probability of getting a multiple of 2 in a throw of an unbiased die is $\frac{1}{2}$.

1. True

2. False

Q. If a die is thrown once, the probability of getting a composite number on the die will be 1/3.

1. True
2. False

Q. Sum of probabilities of all the elementary events of an experiment is ____.

1. 0
2. 0.75
3. 1
4. 0.5

Q.

A bag contains $5$ black, $7$ red, and $3$ white balls. A ball is drawn from the bag at random. Find the probability that the ball drawn is red, black or white and not a black one.

Q.

Elementary events have only one outcome.

1. False

2. True

Q. a) Two coins are tossed once. Find the probability of getting:
i) 2 heads
ii) at least 1 tail.

b)
From a pack of 52 playing cards all cards whose numbers are multiples of 3 are removed. A card is now drawn at random. What is the probability that the card drawn is:
(i) a face card (King, Jack or Queen)
(ii) an even-numbered red card?

[6 MARKS]

Q.

Elementary events are the events which have only one outcome.

1. True

2. False