Answer:
For this data set: 
Mean: (3+3+4+4+4+5+5+5+5+30) : 10 = 6.8 
Mode : 5 
Median : (4+5) : 2 =4.5 
In this case, the mean is not the best way to show central tendency. 
The median is less affected by outliers and skewed data. 
Answer: The best measure for the central tendency is the median: 4.5 
Explanation: