Probability-Lesson G5 G6
Before talking about probability, we will learn about some important definitions which are given below:
2.Unlikely Events: events which may not happen or which is not likely to happen, such as tossing 5 heads in a row, getting 7 fours in a row after rolling a die.
3.Impossible Events: an event that cannot happen such as getting 7 after rolling a die, getting both head and tail after tossing a coin. Probability of an impossible event is 0.
(C) Mutually exclusive events: the events which cannot happen at the same time, such as getting head or tail on a coin (both cannot occur at same time), getting any number from 1 to 6 on a die (only one number occurs after rolling a die.)
--Lesson by The Study Zone
Experiment: an experiment or trial is any procedure that can be infinitely repeated and has a well-defined set of possible outcomes, known as the sample space. In simple words an Experiment is any activity with an observable result, such as tossing a coin, rolling a dice etc.
Outcome: outcome is the result of a single trial of an experiment, such as head or tail on a coin, numbers 1 to 6 on a dice etc.
Event: an event is one or more outcome or result of an experiment, such as getting a head on coin, getting any number on a dice etc.
Probability is the chances or likelihood of the occurrence of an event. The probability of event E can be written as P(E). Probabilities are always numbers between 0 and 1, inclusive i.e.
\(\mathbf{0}\le{P}({E})\le\mathbf{1}\)
Formula to find the Probability:
\(P\left(E\right)=\frac{Number\ of\ ways\ an\ event\ can\ happen}{Total\ number\ of\ possible\ outcomes}\)
Example: A coin is tossed ones. What are the possible outcomes?
What is the probability of each outcome?
Solution: in this example, tossing a coin is the Experiment and possible outcomes are Head (H) and Tail (T)
number of ways that Head or Tail can occur = 1
Total number of possible outcomes = H, T= 2
So, Total number of possible outcomes = 2
\(P\left(H\right)=\frac{number\ of\ ways\ head\ can\ happen}{Total\ number\ of\ possible\ outcomes}\)
\(P\left(H\right)=\frac{1}{2}\)
\(P\left(T\right)=\frac{number\ of\ ways\ Tail\ can\ happen}{Total\ number\ of\ possible\ outcomes}\)
\(P\left(T\right)=\frac{1}{2}\)
Types of events: Events in a probability are of following types:
(1) Likely
(2) Unlikely
(3) Impossible
(4) Certain
1.Likely Events: events which have same probability to happen, such as getting head and tail after tossing a coin, when a die is tossed each number has same chances to happen.
4.Certain Events: an event which is sure to happen, such as getting head or tail on a coin, getting a number from 1 to 6 on a die. Probability of a certain event is 1.
Events can also be:
(B) Independent Events: the events which are not affected by previous event, such as tossing a coin many times does not affect the probability of getting head or tail on next toss.
(A) Dependent events
(A) Dependent Events: the events which are affected by previous event, such as drawing two cards from a deck.
In this case, after drawing first card, there will be less cards in the deck and probabilities will change.
(C) Mutually exclusive events: the events which cannot happen at the same time, such as getting head or tail on a coin (both cannot occur at same time), getting any number from 1 to 6 on a die (only one number occurs after rolling a die.)
--Lesson by The Study Zone
Quiz- 1 G4
Complete this multiple choice quick test to review your knowledge about pattern and addition:
Angles- G4 WS1
Try to count the different types of angles, check this worksheets:
If you need any help with the types of angles, go to this link.
If you need any help with the types of angles, go to this link.