Probability of an Event "A" Not to Happen

Q.

In a cricket match, a batsman hits a boundary 6 times out of the 30 balls he plays. Find the probability of him not hitting a boundary on the balls he plays.

1. 0.2

2. 0.8

3. 0.6

4. 0.4

Q.

A bag contains 12 balls of which 'x' are white.
(i) If one ball is drawn at random, what is the probability that it will be a white ball?
(ii) If 6 more white balls are put in the bag, the probability of drawing a white ball will be double than that in case (i), Find x. [4 MARKS]

Q. A bag contains white, black and red balls only.A ball is drawn at random from the bag.If the probability of getting a white ball is $\frac{3}{10}$ and that of a black ball is $\frac{2}{5}$, then find thew probability of getting a red ball.if the ball bag contains 20 black balls, then find the total number of balls in the bag.

Q.

Six cards are drawn simultaneously from a pack of playing cards. What is the probability that $3$ will be red and $3$ black

1. ${}^{26}C_6$

2. $\frac{{}^{26}C_3}{{}^{52}C_6}$

3. $\frac{{}^{26}C_3·{}^{26}C_3}{{}^{52}C_6}$

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

Q.

A bag contains $4$white, $5$black, and $6$red balls. If a ball is drawn at random, then what is the probability that the drawn ball is either white or red

1. $\frac{4}{15}$

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

3. $\frac{2}{5}$

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

Q.

A jar contains 24 marbles of which some are green and others are blue. If a marble is drawn randomly from the jar, the probability that it is green is $\frac{2}{3}$. Find the probability of drawing a blue marble from the jar.

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

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

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

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

Q.

Out of 100 balls in a bag 30 are green, 35 are blue and 35 are red. Find the probability that a ball drawn from the bag is (i) green (ii) blue (iii) red.

Q.

Two dice are thrown simultaneously. What is the probability of not getting the same numbers on both the dice?

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

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

3. $\frac{5}{6}$

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

Q. A bag contains 7 white, 6 red and 2 black balls. One ball is taken out at random. Find the probability that the ball drawn is:
i) white
ii) neither red nor white
iii) either white or red or black
iv) not black
[4 MARKS]

Q.

A regular hexagon is drawn with its vertices on a circle as shown in the figure. Without looking into it, if one randomly puts a dot in it, what is the probability of the dot not being in the regular hexagon?

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

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

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

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

Q.

A bag contains three green marbles, four blue marbles, and two orange marbles. If a marble is picked at random, then the probability that it is not an orange marble is

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

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

3. $\frac{4}{9}$

4. $\frac{7}{9}$

Q.

Out of all the two digit numbers, what is the probability of the number not being a perfect square?

1. $\frac{14}{15}$

2. $\frac{14}{18}$

3. $\frac{12}{15}$

4. $\frac{1}{15}$

Q.

A bag contains 12 balls of which '$x$' are white.
(i) If one ball is drawn at random, what is the probability that it will be a white ball?
(ii) If 6 more white balls are put in the bag, the probability of drawing a white ball will be double than that in case (i), Find $x$. [4 MARKS]

Q. What is the probability of picking a red numbered card with number more than 6?

1. $\frac{4}{13}$
2. $\frac{2}{13}$
3. $\frac{5}{13}$
4. $\frac{6}{13}$

Q.

A bag contains 4 red and 8 blue marbles. A marble is drawn at random. The probability of drawing red is

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

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

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

4. $\frac{1}{8}$

Q. How do you write the probability value of $0.05$ in percentage format?

1. $5\%$
2. $50\%$
3. $25\%$
4. None of the above

Q.

A bag contains 3 red balls, 5 black balls, and 4 white balls. A ball is drawn at random from the bag. What is the probability of not getting a black ball?

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

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

3. $\frac{7}{12}$

4. 1

Q. The probability of getting a perfect square number in a single throw of a dice is ____.

1. 1/2

2. 
   1/3

3. 
   2/3

4. 
   3/4

Q. Question 26
A school has five houses A, B, C, D and E. A class has 23 students, 4 from house A, 8 from house, B, 5 from house C, 2 from house D and rest from house E. A single student is selected at random to be the class monitor. The probability that the selected student is not from A, B and C is
(a) $\frac{4}{23}$
(b) $\frac{6}{23}$
(c) $\frac{8}{23}$
(d) $\frac{17}{23}$

Q.

If the probability of a day being rainy is 0.75, then the probability of it not being a rainy day is ___.

1. 0.50

2. 0.75

3. 0.25

4. 0

Q.

An equilateral triangle is drawn with its vertices if we put a dot in it without looking into the picture, find the probability of the dot being outside the triangle?

Q. The probability of a day being rainy is 0.75, then the probability of it not being a rainy day is .

1. $0.79$
2. $0.25$
3. $0.50$
4. $0.36$

Q. If the probability of an event is 0.6, then the probability of the event not happening is 0.4.

1. False
2. True

Q. Tickets numbered $2,3,4,5,.....,100,101$ are placed in a box and mixed thoroughly. One ticket is drawn at random from the box. Find the probability that the number on the ticket is a number which is a perfect square.

Q. The probability of getting a perfect square number in a single throw of a dice is ____.

1. 1/2

2. 
   1/3

3. 
   2/3

4. 
   3/4

Q.

In a cricket match, a batsman hit a boundary 6 times (out of 30 balls). Find the probability that next ball he plays is not a boundary.

1. 0.2

2. 0.4

3. 0.6

4. 0.8