Complementary Event

Q. A lot consists of 144 ball pens of which 20 are defective and the others are good. Nuri will buy a pen if it is good, but will not buy if it is defective. The shopkeeper draws one pen at random and gives it to her. What is the probability that she will buy it?
$\left[2Marks\right]$

Q.

The probability of a person winning a game is 0.8, the probability of him losing a game is__.

Q.

In a cricket match , the player hits a 4 in every 12 balls. What is the probablity of him not hitting a 4 .

1. $1$

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

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

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

Q.

A bag contains 8 red, 2 black and 7 white balls. One ball is drawn at random. The probability that the ball drawn is not white is

1. $\frac{5}{17}$

2. $\frac{10}{17}$

3. $\frac{2}{17}$

4. $\frac{8}{17}$

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. $\frac{1}{4}$

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

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

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

Q.

If the probability of an event happening is x, then the probability of event not happening is___

1. x + 1

2. 1/x

3. x - 1

4. 1 - x

Q.

Which of the following is not a complementary event?

1. Probability of finding red balls in a bag having green and red balls only.

2. Probability that the topper of the school is boy or a girl (if only two sexes are considered).

3. Probability of finding a student inside or outside the class on a school day.

4. None of these

Q. The probability of an event not happening is 0.95, then the probability of the event happening is ___

1. 0.5
2. 0.05
3. 0.25
4. 5

Q.

The probability of guessing the correct answer to certain test questions is $\frac{y}{4}$. If the probability of not guessing the correct answer to these questions is $\frac{3}{4}$, then the value of y is:

1. 1

2. 0

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

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

Q.

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

1. 

2. 

3. 

4.