Answer:
--- 20th percentile
--- 25th percentile
--- 65th percentile
--- 75th percentile
Step-by-step explanation:
Given
27, 24, 21, 16, 30, 33, 28, and 24.
N = 8
First, arrange the data in ascending order:
Arranged data: 16, 21, 24, 24, 27, 28, 30, 33
Solving (a): The 20th percentile
This is calculated as:
![P_{20} = 20 * \frac{N +1}{100}](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%2020%20%2A%20%5Cfrac%7BN%20%2B1%7D%7B100%7D)
![P_{20} = 20 * \frac{8 +1}{100}](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%2020%20%2A%20%5Cfrac%7B8%20%2B1%7D%7B100%7D)
![P_{20} = 20 * \frac{9}{100}](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%2020%20%2A%20%5Cfrac%7B9%7D%7B100%7D)
![P_{20} = \frac{20 * 9}{100}](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%20%5Cfrac%7B20%20%2A%209%7D%7B100%7D)
![P_{20} = \frac{180}{100}](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%20%5Cfrac%7B180%7D%7B100%7D)
![P_{20} = 1.8th\ item](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%201.8th%5C%20item)
This is then calculated as:
![P_{20} = 1st\ Item +0.8(2nd\ Item - 1st\ Item)](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%201st%5C%20Item%20%2B0.8%282nd%5C%20Item%20-%201st%5C%20Item%29)
![P_{20} = 16 + 0.8*(21 - 16)](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%2016%20%2B%200.8%2A%2821%20-%2016%29)
![P_{20} = 16 + 0.8*5](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%2016%20%2B%200.8%2A5)
![P_{20} = 16 + 4](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%2016%20%2B%204)
![P_{20} = 20](https://tex.z-dn.net/?f=P_%7B20%7D%20%3D%2020)
Solving (b): The 25th percentile
This is calculated as:
![P_{25} = 25 * \frac{N +1}{100}](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%2025%20%2A%20%5Cfrac%7BN%20%2B1%7D%7B100%7D)
![P_{25} = 25 * \frac{8 +1}{100}](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%2025%20%2A%20%5Cfrac%7B8%20%2B1%7D%7B100%7D)
![P_{25} = 25 * \frac{9}{100}](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%2025%20%2A%20%5Cfrac%7B9%7D%7B100%7D)
![P_{25} = \frac{25 * 9}{100}](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%20%5Cfrac%7B25%20%2A%209%7D%7B100%7D)
![P_{25} = \frac{225}{100}](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%20%5Cfrac%7B225%7D%7B100%7D)
![P_{25} = 2.25\ th](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%202.25%5C%20th)
This is then calculated as:
![P_{25} = 2nd\ item + 0.25(3rd\ item-2nd\ item)](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%202nd%5C%20item%20%2B%200.25%283rd%5C%20item-2nd%5C%20item%29)
![P_{25} = 21 + 0.25(24-21)](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%2021%20%2B%200.25%2824-21%29)
![P_{25} = 21 + 0.25(3)](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%2021%20%2B%200.25%283%29)
![P_{25} = 21 + 0.75](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%2021%20%2B%200.75)
![P_{25} = 21.75](https://tex.z-dn.net/?f=P_%7B25%7D%20%3D%2021.75)
Solving (c): The 65th percentile
This is calculated as:
![P_{65} = 65 * \frac{N +1}{100}](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%2065%20%2A%20%5Cfrac%7BN%20%2B1%7D%7B100%7D)
![P_{65} = 65 * \frac{8 +1}{100}](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%2065%20%2A%20%5Cfrac%7B8%20%2B1%7D%7B100%7D)
![P_{65} = 65 * \frac{9}{100}](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%2065%20%2A%20%5Cfrac%7B9%7D%7B100%7D)
![P_{65} = \frac{65 * 9}{100}](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%20%5Cfrac%7B65%20%2A%209%7D%7B100%7D)
![P_{65} = \frac{585}{100}](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%20%5Cfrac%7B585%7D%7B100%7D)
![P_{65} = 5.85\th](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%205.85%5Cth)
This is then calculated as:
![P_{65} = 5th + 0.85(6th - 5th)](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%205th%20%2B%200.85%286th%20-%205th%29)
![P_{65} = 27 + 0.85(28 - 27)](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%2027%20%2B%200.85%2828%20-%2027%29)
![P_{65} = 27 + 0.85(1)](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%2027%20%2B%200.85%281%29)
![P_{65} = 27 + 0.85](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%2027%20%2B%200.85)
![P_{65} = 27.85](https://tex.z-dn.net/?f=P_%7B65%7D%20%3D%2027.85)
Solving (d): The 75th percentile
This is calculated as:
![P_{75} = 75 * \frac{N +1}{100}](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%2075%20%2A%20%5Cfrac%7BN%20%2B1%7D%7B100%7D)
![P_{75} = 75 * \frac{8 +1}{100}](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%2075%20%2A%20%5Cfrac%7B8%20%2B1%7D%7B100%7D)
![P_{75} = 75 * \frac{9}{100}](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%2075%20%2A%20%5Cfrac%7B9%7D%7B100%7D)
![P_{75} = \frac{75 * 9}{100}](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%20%5Cfrac%7B75%20%2A%209%7D%7B100%7D)
![P_{75} = \frac{675}{100}](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%20%5Cfrac%7B675%7D%7B100%7D)
![P_{75} = 6.75th](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%206.75th)
This is then calculated as:
![P_{75} = 6th + 0.75(7th - 6th)](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%206th%20%2B%200.75%287th%20-%206th%29)
![P_{75} = 28 + 0.75(30- 28)](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%2028%20%2B%200.75%2830-%2028%29)
![P_{75} = 28 + 0.75(2)](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%2028%20%2B%200.75%282%29)
![P_{75} = 28 + 1.5](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%2028%20%2B%201.5)
![P_{75} = 29.5](https://tex.z-dn.net/?f=P_%7B75%7D%20%3D%2029.5)