Question 1 :
This semester, Gerry scored an average of $93$ on his five history exams. He got the same score on his first two exams, and then he got a $94$, an $85$, and a $90$ on the remaining exams. What score did he receive on his first two exams?
Question 2 :
The mean of the numbers $a,b,c, d$ and $e$ is $23$. The mean of the numbers $a,b,c,d,e$ and $f$ is $22$. What is the value of $f$?
Question 3 :
Wheat was purchases in the fist year at Rs 9 / kg in second year at Rs 10/kg and in the third year at Rs 11/kg ,if each year Rs 990 were spend in purchasing wheat the average cost of wheat during the three year is nearly 
Question 4 :
A grocer has a sale of $Rs. 6435, Rs. 6927, Rs. 6855, Rs. 7230$ and $Rs. 6562$ for $5$ consecutive months. How much sale must he have in the sixth month so that he gets an average sale of $Rs. 6500$?<br>
Question 5 :
The following data has been arranged in ascending order. If their median is $63$, find thevalue of $ x\ : $<br>$34,37,53,55,x,x+ 2,77,83,89 $ and $100$<br>
Question 6 :
The mean of $4, y, 6, x$ and $12$ is $6$. Then-
Question 7 :
Mean of $31$ observation is $65$ .If mean of first $15$ observation is $64$ and that of last $15$ observation is $66$ ,then the sixteenth observation is 
Question 8 :
If the mean of five observations $x, x + 2 , x + 4, x+ 6$ and $x + 8$ is $11$, then the mean of last three observations is
Question 9 : If the arithmetic mean of the following data is $7$, then $a+b$ =<br><br><table class="wysiwyg-table"><tbody><tr><td>$x_i$</td><td>4</td><td>6</td><td>7</td><td>9</td></tr><tr><td>$f_i$</td><td>$a$</td><td>4</td><td>$b$</td><td>5</td></tr></tbody></table>
Question 10 :
Mean weight of 25 students of a class is 60 kg. If mean weight of first 13 students is 57 kg and that of last 13 students is 63 kg, then the weight of the 13th students is 
Question 11 :
There are four natural numbers. The average of any three numbers is added in the fourth number and in this way, the numbers $29, 23, 21$and $17$ are obtained. One of the numbers is
Question 12 :
Mean weight of 21 boys is 40 kg ,if mean of first 10 boys is 42 kg and that of last 10 boys is 38 kg ,then weight of the 11th boy is 
Question 13 :
The average of marks of $12$ students is $15$. The marks of a student who scored zero were wrongly taken as $18$ and average was determined. The correct average marks is _________.
Question 14 :
The average weight of three men A, B and C is 84 kg, Another man D joins the group and the average now becomes 80 kg, if another man E whose weight is 3 kg more than that of D replace A, than the average weight of B, C D and E becomes 79 kg. The weight of A is 
Question 15 :
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 16 :
A student obtained the following marks percentage in an examination English - 50, Accounts - 75, Economics - 60, B. Std. - 80 Hindi - 55 If weights are 2, 3, 3, 2, 1 respectively allotted to the subjects his weighted mean is
Question 17 :
The average of five results is$46$ and that of the first four is $45$, fifth result is ?
Question 18 :
The average age of 3 friends is 23. Even if the age of the 4th friend is added, the average remains 23. What is the age of the 4th friend?
Question 19 :
The average of $6$ observations is $12$. A new seventh observation is included and the new average is decreased by $1$. The seventh observation is
Question 20 :
The mean of $ x, x+2, x+4, x+6 $ and $ x+8$ is $11.$ find the mean of the first three observations.<br>
