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Thus, the required mean of the given observation is 25.6.
Example 6: A batsman scored the following runs in six innings: 126, 35, 55, 66, 39, 57

Find the average runs scored by the batsman in an inning.
Solution: Total number of innings = 6
Sum of the runs scored by the batsman = 126 + 35 + 55 + 66 + 39 + 57 = 378
We have,
Remember
Sum of all observations
Average runs = The mean of two numbers
Number of observations will always lie between the
378 two numbers.
x = = 63
6
Thus, the required average run-scored by the batsman is 63.
Example 7: Find the mean of first 8 multiples of 3.

Solution: First 8 multiples of 3 = 3, 6, 9, 12, 15, 18, 21, 24
Total number of observations = 8

Sum of the observations (multiples) = 3 + 6 + 9 + 12 + 15 + 18 + 21 + 24 = 108
We have,
Think and Answer
Sum of all observations
Arithmetic mean (A.M.) = Find the mean of your study
Number of observations hours during one week.
108
x = = 13.5
8
Thus, the mean of the first 8 multiples of 3 is 13.5.
Example 8: The weights (in kg) of 8 students in a group are: 34, 36, 28, 41, 36, 44, 29, and 24.
Find the mean weight.
Solution: The weights (in kg) of 8 students in a group are: 34, 36, 28, 41, 36, 44, 29, and 24
Total number of observations = 8
Sum of the observations = 34 + 36 + 28 + 41 + 36 + 44 + 29 + 24
= 272
We have,

Sum of all observations
Arithmetic mean (A.M.) =
Number of observations
272
x = = 34
8
Thus, the required mean weight is 34 kg.

Example 9: In a cinema hall, the records of tickets sold during a week are as follows:

Days Mon Tue Wed Thu Fri Sat Sun

No. of Tickets Sold 145 120 125 135 205 250 300
Find the arithmetic mean of tickets sold.

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