Topics
Linear equations in two variables
- Linear Equations in Two Variables
- Linear Equations in Two Variables Applications
- Cross - Multiplication Method
- Substitution Method
- Elimination Method
- Graphical Method of Solution of a Pair of Linear Equations
- Determinant of Order Two
- Equations Reducible to a Pair of Linear Equations in Two Variables
- Simple Situational Problems
- Inconsistency of Pair of Linear Equations
- Cramer'S Rule
- Consistency of Pair of Linear Equations
- Pair of Linear Equations in Two Variables
Quadratic Equations
- Quadratic Equations Examples and Solutions
- Quadratic Equations
- Roots of a Quadratic Equation
- Nature of Roots
- Relation Between Roots of the Equation and Coefficient of the Terms in the Equation Equations Reducible to Quadratic Form
- Solutions of Quadratic Equations by Factorization
- Solutions of Quadratic Equations by Completing the Square
- Formula for Solving a Quadratic Equation
Arithmetic Progression
- Introduction to Sequence
- Geometric Mean
- Arithmetic Progression Examples and Solutions
- Arithmetic Progression
- Geometric Progression
- General Term of an Arithmetic Progression
- General Term of an Geomatric Progression
- Sum of First n Terms of an AP
- Sum of the First 'N' Terms of an Geometric Progression
- Arithmetic Mean - Raw Data
- Terms in a sequence
- Concept of Ratio
Financial Planning
Probability
- Basic Ideas of Probability
- Probability - A Theoretical Approach
- Type of Event - Elementry
- Type of Event - Complementry
- Type of Event - Exclusive
- Type of Event - Exhaustive
- Equally Likely Outcomes
- Probability of an Event
- Concept Or Properties of Probability
- Addition Theorem
- Random Experiments
- Sample Space
- Basic Ideas of Probability
Statistics
- Tabulation of Data
- Inclusive and Exclusive Type of Tables
- Median of Grouped Data
- Mean of Grouped Data
- Graphical Representation of Data as Histograms
- Frequency Polygon
- Concept of Pie Graph (Or a Circle-graph)
- Concept of Pie Graph (Or a Circle-graph)
- Ogives (Cumulative Frequency Graphs)
- Applications of Ogives in Determination of Median
- Relation Between Measures of Central Tendency
- Introduction to Normal Distribution
- Properties of Normal Distribution
- Graphical Representation of Data as Histograms
- Mode of Grouped Data
definition
Arithmetic Mean: The mean of a number of observations is the sum of the values of all the observations divided by the total number of observations.
`"Mean" = "Sum of all observations"/"number of observations"`.
notes
Arithmetic Mean:
- Arithmetic mean is one of the representative values of data.
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The mean of a number of observations is the sum of the values of all the observations divided by the total number of observations.
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It is denoted by the symbol x, read as `bar x`.
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The average or Arithmetic Mean (A.M.) or simply mean is defined as follows:
`"Mean" = "Sum of all observations"/"number of observations"`
Example
Two vessels contain 20 liters and 60 liters of milk respectively. What is the amount that each vessel would have if both share the milk equally?
The average or the arithmetic mean would be
= `"Total quantity of milk"/"Number of vessels"`
= `(20 + 60)/2` litres
= 40 litres.
Thus, each vessel would have 40 liters of milk.
Example
Ashish studies for 4 hours, 5 hours, and 3 hours respectively on three consecutive days. How many hours does he study daily on average?
The average study time of Ashish would be
`"Total number of study hours"/"Number of days for which he studied" = (4 + 5 + 3)/3` hours = 4 hours per day
Thus, we can say that Ashish studies for 4 hours daily on an average.
Example
A batsman scored the following number of runs in six innings: 36, 35, 50, 46, 60, 55. Calculate the mean runs scored by him in an inning.
Total runs = 36 + 35 + 50 + 46 + 60 + 55 = 282.
To find the mean, we find the sum of all the observations and divide it by the number of observations.
Therefore, in this case, mean = `282/6` = 47.
Thus, the mean runs scored in an inning is 47.
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Related QuestionsVIEW ALL [9]
Following table shows the points of each player scored in four games:
Player | Game 1 | Game 2 | Game 3 | Game 4 |
A | 14 | 16 | 10 | 10 |
B | 0 | 8 | 6 | 4 |
C | 8 | 11 | Did not play | 13 |
Now answer the following questions:
1) Find the mean to determine A’s average number of points scored per game
2) To find the mean number of points per game for C, would you divide the total points by 3 or by 4? Why?
3) B played in all the four games. How would you find the mean?
4) Who is the best performer?