EXPLANATION
Minimum
The first Quartile is the value separating the lower quarter and higher three - quarters of the data set.
The first quartile is computed by taking the median of the lower half of a sorted set.
Arranging terms in ascending order
40, 42 , 46, 48, 51, 55, 58, 66, 67, 68, 69
Here, we can see that:
Minimum = 40
Maximum = 69
Q2=55 (median)
Taking the lower half of the ascending set:
Counting the number of terms in the data set:
{40, 42 , 46, 48, 51, 55, 58, 66, 67, 68, 69}
{1, 2 , 3, 4, 5, 6, 7, 8, 9, 10, 11}
The number of terms in the data set is:
11
Since the number of terms is odd, take the elements below the middle one, that is, the lower 5 elements.
40, 42 , 46, 48, 51
Median of 40, 42 , 46, 48, 51:
The number of terms in the data set is 5.
Since the number of terms is odd, the median is the middle element of the sorted set.
Q1: 46
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Q3:
Since the number of terms is odd, take the elements above the middle one, that is, the upper 5 elements.
58, 66, 67, 68, 69
The number of terms in the data set is
5
Since the number of terms is odd, the median is the middle element of the sorted set.
Q3=67
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Interquartile Range:
The interquartile range is the difference of the first and third quartiles
We have that:
Q1=46
Q3=67
Computing the difference between 67 and 46:
67-46= 21
Interquartile Range=21
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Answers:
Minimum = 40
Q1=46
Q2=55 (median)
Q3=67
Maximum = 69
Interquartile Range=21