Question

If an event occurs certainly, then its probability will be

• A. $\dfrac{3}{4}$
• B. $\dfrac{1}{2}$
• C. 0
• D. 1

Hint:

Probabilities range from 0 to 1. An impossible event has probability 0, while a certain event has probability 1.

Answer 1

The Correct Option is D

Step 1: Definition of probability.
The probability of an event measures how likely it is to occur, given by the formula: \[ P(E) = \dfrac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} \] Step 2: Case of a certain event.
If an event occurs certainly, then the number of favorable outcomes equals the total number of outcomes. \[ P(E) = \dfrac{n(S)}{n(S)} = 1 \] Step 3: Conclusion.
Hence, the probability of a sure event is always 1.