Fill in the blanks.
Probability of a sure event is ___P___.
Sum of the probabilities of all possible outcomes of an event is _Q_.
Probability of an event cannot be _R_ .

Options

A. 0, 0, Positive
B. 0,1, Fraction
C. 1 ,1,Negative
D. 0 ,1,Less than 1

Answer

To solve the question, we need to fill in the blanks based on the properties of probability.

1. **First Blank (P)**: The probability of a sure event is ___P___.
- A sure event is an event that is certain to happen. The probability of such an event is always 1.
- Therefore, we fill in the first blank with **1**.

2. **Second Blank (Q)**: The sum of the probabilities of all possible outcomes of an event is ___Q___.
- The sum of the probabilities of all possible outcomes of an event must equal 1. This is a fundamental property of probability.
- Thus, we fill in the second blank with **1**.

3. **Third Blank (R)**: The probability of an event cannot be ___R___.
- The probability of an event cannot be negative. Probabilities are always between 0 and 1, inclusive.
- Hence, we fill in the third blank with **negative**.

So, the final answers are:
- P = 1
- Q = 1
- R = negative

### Summary of Answers:
- Probability of a sure event is **1**.
- Sum of the probabilities of all possible outcomes of an event is **1**.
- Probability of an event cannot be **negative**.