Q6. 
Which one of the following numbers can be removed from the set $S$ = {0, 2, 4, 5, 9} without changing the average of set $S$? 
A.  0 

B.  2 

C.  4 

D.  5 
Q7. 
Average cost of 5 apples and 4 mangoes is Rs. 36. The average cost of 7 apples and 8 mangoes is Rs. 48. Find the total cost of 24 apples and 24 mangoes. 
A.  1044 

B.  2088 

C.  720 

D.  324 
Q8. 
Average of ten positive numbers is $x$. If each number is increased by $10\%$, then $x$ : 
A.  remains unchanged 

B.  may decrease 

C.  may increase 

D.  is increased by $10\%$ 
Q10. 
The average salary of all the workers in a workshop is Rs.8000. The average salary of 7 technicians is Rs.12000 and the average salary of the rest is Rs.6000. The total number of workers in the workshop is: 
A.  20 

B.  21 

C.  22 

D.  23 