Find the values of the 30th and 90th percentiles of the data. 18, 9, 7, 5, 11, 7, 17, 20, 19, 2, 17, 12, 5, 1, 13, 12, 11, 15, 16, 20
To find the values of the 30th and 90th percentiles of the data, first, we need to sort the data in ascending order:
1, 2, 5, 5, 7, 7, 9, 11, 11, 12, 12, 13, 15, 16, 17, 17, 18, 19, 20, 20
There are a total of 20 data points, so the 30th percentile would fall at the position:
(30/100) * 20 = 6th position
The 30th percentile value is the 6th data point in the sorted list, which is 7.
The 90th percentile would fall at the position:
(90/100) * 20 = 18th position
The 90th percentile value is the 18th data point in the sorted list, which is 19.
Therefore, the 30th percentile of the data is 7, and the 90th percentile of the data is 19.