Given:
The ages of 18 of the signers of the Declaration of Independence are given as below
44, 35, 30, 35, 40, 38, 50, 49, 39, 52, 60, 46, 42, 43, 31, 33, 48, 42
Find:
we have to find 25th and 60th percentiles for these ages.
Step-by-step explanation:
Arrange the data in ascending order:
30, 31, 33, 35, 35, 38, 39, 40, 42, 42, 43, 44, 46, 48, 49, 50, 52, 60
Now, we will compute the position of the pth percentile (index i):
i = (p / 100) * n), where p = 25 and n = 18
i = (25 / 100) * 18 = 4.5
The index i is not an integer, round up. (i = 5) ⇒ the 25th percentile is the value in 5th position, or 35
Answer: the 25th percentile is 35
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Now,for 60the percentile , we will compute the position of the pth percentile (index i):
i = (p / 100) * n), where p = 60 and n = 18
i = (60 / 100) * 18 = 10.8
The index i is not an integer, round up. (i = 11) ⇒ the 60th percentile is the value in 11th position, or 43
Answer: the 60th percentile is 43