Answer:
Step-by-step explanation:
Hello!
The variable of interest is
X: mark obtained in an aptitude test by a candidate.
This variable has a mean μ= 128.5 and standard deviation σ= 8.2
You have the data of three scores extracted from the pool of aptitude tests taken.
148, 102, 152
The average is calculated as X[bar]= Σx/n= (148+102+152)/3= 134
An outlier is an observation that is significantly distant from the rest of the data set. They usually represent experimental errors (such as a measurement) or atypical observations. Some statistical measurements, such as the sample mean, are severely affected by this type of values and their presence tends to cause misleading results on a statistical analysis.
Using the mean and the standard deviation, an outlier is any value that is three standard deviations away from the mean: μ±3σ
Using the population values you can calculate the limits that classify an observed value as outlier:
μ±3σ
128.5±3*8.2
(103.9; 153.1)
This means that any value below 103.9 and above 153.1 can be considered an outlier.
For this example, there is only one outlier, that this the extracted score 102
I hope this helps!
