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 N 1  th
th
Median = value of   item = item = 6 item = 5
 2 

Example-2: The following data have been arranged in ascending order:
24, 27, 28, 31, 34, x, 37, 40, 42, 45
If the median of the data is 35, find ''x'' in the above data.
Solution: Total terms are 10, Here n = 10 = even, there are two middle terms 34 and x
Two middle terms are 34 and x.

Median =
or, 34 + x = 35 2
or, 34 + x = 70
or, x = 70 – 34 = 36

Example-3:The median of the following observations arranged in ascending order
is 24. Find x.
11, 12, 14, 18, x + 2, x + 4, 30, 32, 35, 41

Solution:Total number of observations = 10
Therefore, Median of the observations is the mean of the 5th and 6th observations.

Therefore, Median

= x + 3
Median = 24 (given)
Therefore, x + 3 = 24
Therefore, x = 24 - 3 = 21

Cumulative Frequency

Frequency: The number of times an observation occurs is known as frequency.

Cumulative Frequency: Cumulative Frequency of a class is defined as the sum of all
frequencies upto the given data.

The cumulative frequency is usually observed in constructing a cumulative frequency
table.

Example-4:Make a cumulative frequency table for the given distribution.
Marks 50-60 40-50 30-40 20-30 10-20 0-10

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