The third quartile value for the given data 20,21,24,25,28,29,35,37,42 is 36.
The median is the middle value of a data which is arranged in either ascending/descending order.
The lower/first quartile is the median of the bottom half of the data.
The higher/third quartile is the median of the upper half of the data.
Arranging the given sequence in ascending order:
20,21,24,25,28,29,35,37,42
Calculating the median of this sequence:
Median(odd no. of terms) = ((n+1)/2)th term
Median(9 terms) = ((9+1)/2)th term
Median = 5th term
Median = 28
Now, the upper half of the data is:
29,35,37,42
Median(even no. of terms) = Median of the two middle terms
Median = ((35+37)/2)
Median = 36
Hence the third quartile of the given data is 36
Learn more about quartiles here:
https://brainly.com/question/1382117
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