CERTAIN EVENT
Definition Of Certain Event
An event that is certain to occur is called Certain Event.
More About Certain Event
The probability of a certain event is always 1.
Example of Certain Event
The Christmas will be celebrated on the 25th of December this year. This is a certain event.
It is 2:00 p.m. now and will be 4:00 p.m. after two hours. This is a certain event.
Video Examples: icoachmath works
Solved Example on Certain Event
Ques: A teacher chooses a student at random from a class of 30 boys. What is the probability that the student chosen is a boy?
Choices:
A.1/30
B.1/29
C. 0
D. 1
Correct Answer: D
Solution:
Step 1: Number of students in a class is 30. So, the number of possible outcomes is 30.
Step 2: Since all the students in the class are boys, the number of favorable outcomes is 30.
Step 3: Probability (event) = 
[Formula.]
Step 4: P (boy) =30/30 = 1 [Substitute the values.]
Step 5: The probability that the student chosen is a boy is 1.
Quick Summary
- Probability of a certain event is always 1.
- Certain events are sure to happen.
🍎 Teacher Insights
Use real-world examples, such as the sun rising in the east, to illustrate the concept of a certain event.🎓 Prerequisites
- Basic Probability
- Understanding of Events
Check Your Knowledge
Q1: A bag contains only red balls. What is the probability of picking a red ball?
Q2: What is the probability that the day after Saturday is Sunday?
Frequently Asked Questions
Q: What is the probability of a certain event?
A: The probability of a certain event is always 1.
Q: Can an event be 'more' certain than another?
A: No, if an event is certain, its probability is exactly 1. There are no degrees of certainty beyond that.