Complementary Event

Q.

In an entrance test there are multiple choice questions. There are four possible answers to each question of which one is correct. The probability that a student knows the answer to a question is $90\%$. If he gets the correct answer to a question, then the probability that he was guessing is:

1. $\frac{37}{40}$

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

3. $\frac{36}{37}$

4. $\frac{1}{9}$

Q.

If the probability of winning a game is $0.3$, then what is the probability of losing it?

Q.

There are seven marbles in a box with numbers from $1$ to $7$ marked on each of them. The probability of drawing a marble with the number $6$ is $\underline{}$ $.$

Q.

Three letters are drawn from alphabets of $26$ letters without replacement. The probability that letters appear orderly is

Q.

If P(A) = 0.15, then P(not A) =

1. 0.35

2. 0.3

3. 0.85

4. Cannot be determined

Q.

If the probability of a student writing the right answer to a question is $\frac{1}{5}$, then the probability of the student writing a wrong answer is $\frac{4}{5}$.

1. False

2. True

Q. If x - 5 = 10, then x = 15.

1. True
2. False

Q. If x - 5 = 10, then x = 15.

1. True
2. False

Q. If P(E) = 0.05, what is the probability of ‘not E’___

Q.

The probability of an event occurring is 0.7. The probability of that event not occuring is __. Please give the decimal value.