Question 2 :
Emmy did a survey of how many games each of $20$ friends owned, and got the following data: $5, 7, 12, 13, 4, 6, 8, 12, 9, 16, 13, 12, 5, 13, 7, 17, 3, 9, 12, 14.$ Find the mean.<br/>
Question 5 :
Which average shows the most common variable in the data set?
Question 6 :
The mean of $n$ items is $\overline { X }$ . If first item is increased by $1$ second item by $2 ,$ and so on, then new mean is :
Question 7 :
Seven of the eight numbers in a distribution are $11, 16,6, 10, 13, 11, 13.$<br/> Given that the mean of the distribution is $12$,if 12 will be included then find the new mean of the distribution. 
Question 8 :
If the values $1, \dfrac{1}{2}, \dfrac{1}{3}, \dfrac{1}{4}, \dfrac{1}{5},....\dfrac{1}{n}$ occur at frequencies $1, 2, 3, 4, 5, 6..., n$ respectively, in a frequency distribution, then the mean is
Question 9 :
When there are 2 observations in the middle, median is calculated by ______.
Question 10 :
The mean of 100 numbers is 45. The mean of the last 99 numbers is 44. The first number is