Vidya Kumari TGT-Maths

1. Probability

2. What is Probability?•Probability is the measure of how likely an event or
outcome is.
•Different events have different probabilities!
Definition Of Theoretical Probability
P(E)= No. of Favorable outcomes
Total no. of outcomes
Where E = event

3. How do we express Probabilities?
Usually, we express probabilities as fractions.
1. The numerator shows the POSSIBLE number
of ways an event can occur.
2. The denominator is the TOTAL number of
possible events that could occur.

4. Some common terms related to Probability
Experiment: It is a situation involving chance or probability that
leads to results called outcomes.
Event: Number of outcomes in an experiment.
Outcome: A possible result of a random experiment.

5. Probability- General Rules
1. Probability is a number between 0 and 1.
2. The sum of the probabilities of all possible
outcomes in a sample space is 1.
3. The probability that an event does not
occur is 1 minus the probability that it does
occur. (also called the complement of A)
P(not E) = 1- P(E)

6. For example
The chance of a coin landing on
heads is 50%. This is because a
coin has two sides so there is a
50% chance that the coin will
land on heads and 50% that a
coin will land on tails.

7. Where is Probability Used?
Probability is used a lot in daily life, Probability is used
in such as Math, Statistics, Finance, Gambling,
Science, Machine and Artificial Intelligence, and in
many other activities.

8. When question arises related
to chance of something
happening , you are dealing
with probability.

9. In this bag of marbles, there are:
3 red marbles
2 white marbles
1 purple marble
4 green marbles

10. 1. How many red marbles are in the bag?
Solution:-3/10 or 0.3
2. How many Green marbles are there in the bag?
Solution:-4/10 = 2/5 or 0.4

11. Thank You