An administrator wanted to study the utilization oflong-distance telephone service by a department. One variable ofinterest (let’s call it X) is the length, in minutes, oflong-distance calls made during one month. There were 38 calls thatresulted in a connection. The length of calls, already ordered fromsmallest to largest, are presented in the followingtable.
1.6 | 1.7 | 1.8 | 1.8 | 1.9 | 2.1 | 2.5 | 3.0 | 3.0 | 4.4 |
4.5 | 4.5 | 5.9 | 7.1 | 7.4 | 7.5 | 7.7 | 8.6 | 9.3 | 9.5 |
12.7 | 15.3 | 15.5 | 15.9 | 15.9 | 16.1 | 16.5 | 17.3 | 17.5 | 19.0 |
19.4 | 22.5 | 23.5 | 24.0 | 31.7 | 32.8 | 43.5 | 53.3 | | |
Which one of the following statements is nottrue?
The 75th percentile (Q3) is 17.5 minutes.
The 50th percentile is (Q2) 9.4 minutes.
The 25th percentile (Q1) is 4.4 minutes.
Q3- Q2 > Q2- Q1
Average X > Median X.
X distribution is positively skewed.
The percentile rank of 5.9 minutes is 13.
Range of X is 51.7 minutes.
IQR (Inter-Quartile Range) is 13.1 minutes.
There are 2 outliers in X distribution.
Q4: (This continues Q3: 2 marks) Which one of thefollowing cannot be used to describe the distribution ofX?
A Histogram.
A Stemplot.
Skewness and Kurtosis.
Mean and SD (Standard Deviation).
The 5-number Summary.
The coefficient of determination.
The coefficient of relative variation(CRV).
The 1.5 IQR Rule.
The Deciles.
A Boxplot.
