Question 1 :
The mean of $ x, x+2, x+4, x+6 $ and $ x+8$ is $11.$ find the mean of the first three observations.<br>
Question 2 :
The daily sale of milk (in litres) in a ration shop for eight days is as follows-<br>$60, 40, 10, 40, 4, 70, 30$ and $10$. The average daily sale is-
Question 3 :
In the formula for mode of a grouped data, mode $=l+\left \{\dfrac {f_1-f_0}{2f_2-f_0-f_2}\right \}\times h$, where symbols have their usual meaning $f_0$ represents<br/>
Question 4 :
Mean of 100 values was calculated as 155. On checking it was discovered that 42 and 26 were wrongly copied as 22 and 16. The correct means is 
Question 5 :
Find the average of all the number between $6$  and $34$  which are divisible by  $5$.
Question 6 :
The sum of $12$ observations is $600$ then their mean is _____
Question 10 :
The attendance of a class of 45 boys for 10 days is given as 40, 30, 35, 45, 44, 41, 38, 44 and 41 then the mean attendance of a class is
Question 11 :
If the mean of first $ n$ odd natural number be $n$ , then mean of first $2n$ odd natural numbers be 
Question 12 :
Mode of the distribution is that value of the variate for which the_____is_____
Question 13 :
The weights in kilogram of 9 members in a school boxing team are 54, 59, x, 53, 73,49, 50, 58, 45 If the average is 56 then x is
Question 14 :
If the mean of $x+2$, $2x+3$, $3x+4$, $4x+5$ is $x+2$, then $x$ is equal to
Question 17 :
Mean of a set of 23 values is 7, if each value is multiplied by 23 the new mean is 
Question 19 :
The mean of 30, 32, 24, 34, 26, 28, 30, 35, 33, 25 is 29.7<br/>If true then enter $1$ and if false then enter $0$<br/>
Question 21 :
The average weight of a group of 20 boys was calculated to be 89.4 kg and it was later discovered that one weight was misread as 78 kg instead of 87 kg. The correct average weight is
Question 22 :
If the arithmetic mean of $5, 7, 9, x$ is $9$, then the value of $x$ is 
Question 23 :
The mean weight of $150$ students in a certain class is$ 60$ kg. The mean weight of boys in the class is $70$ kg. and that of the girls is$ 55 $kg., the ratio of boys and girls respectively is 
Question 24 :
The weight of a body, calculated as the average of seven different experiments is $53.735$ g. The average of the first three experiments is $54.005$ g. The fourth was greater than the fifth by $0.004$ g and the average of sixth and seventh was $0.010$ g less than the average of the first three. Find the weight of the body in the fourth experiment. 
Question 25 :
The following data has been arranged in ascending order. If their median is $63$, find the value of $ x\ : $<br>$34,37,53,55,x,x+ 2,77,83,89 $ and $100$<br>
Question 26 :
The mean of $1, 2, 3,\cdots \left ( n+1 \right )is\ \dfrac{6n}{11}$, then the value of n equals
Question 27 :
The _____ of a set of data is the middlemost number in the set.<br>
Question 28 :
The median $31, 16,19, 25, 14, 13,12, 4, 28, 45$ is 
Question 29 :
If the median of $\displaystyle \frac{x}{5}$ $\displaystyle x$ $\displaystyle \frac{x}{4}$ $\displaystyle \frac{x}{2}$ and $\displaystyle \frac{x}{3}$ $\displaystyle \left ( where\, x> 0 \right )$ is $8$ then the value of $x$ would be
Question 30 :
Of the three numbers, the first is twice the second, and the second is twice the third. The average of the reciprocal of the numbers is $\displaystyle \frac{7}{72}$. What are the three numbers ?
Question 31 :
The mean of the following data is :<br/>$45, 35, 20, 30, 15, 25, 40$<br/>
Question 33 :
The mean of the squares of the first n natural numbers is
Question 34 :
The mean of $6$ numbers is $42$ If one number is excluded, the mean of remaining numbers is $45$. Find the excluded number.<br/>
Question 35 :
The sum $\displaystyle \sum _{ r=1 }^{ 10 }{ \left( { r }^{ 2 }+1 \right) \times \left( r\ ! \right) }$ is equal to:
Question 36 :
The average sales of Saraswati Motors from January to June are $150\ units$. Its average sales from July to October are $240\ units$. What is the average sales (in units) for the months November and December, if the average sales for the year are $200\ units$?
Question 38 :
Find the mean of the following data :<br/>$30, 32, 24, 34. 26, 28, 30. 35, 33, 25$
Question 39 :
Let set $M = \left \{x, 2x, 4x\right \}$ for any number $x$. If the average (arithmetic mean) of the numbers in set $M$ is $14$, find the value of $x$.
Question 40 : <table class="wysiwyg-table"><tbody><tr><td>x</td><td>10</td><td>15</td><td>20</td><td>25</td><td>35</td></tr><tr><td>f</td><td>6</td><td>p</td><td>26</td><td>10</td><td>8</td></tr></tbody></table>If means of the above is 21 then values of p is
