Question: 1 -

The mean of 40 observations was 46. Later on it was found that an observation 38 was wrongly taken as 33. find the corrected value of mean.

42.36

46.12

40.23

51.23

Answer:

46.12

Solution:

Average =Sum of Quantities/Number of Quantities

Question: 2 -

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? 

Rs. 6991

Rs. 5991

Rs. 4991

Rs. 6001

Answer:

Rs. 4991

Solution:

Total sale for 5 months = Rs. (6435 + 6927 + 6855 + 7230 + 6562) = Rs. 34009.
Required sale = Rs. [ (6500 x 6) - 34009 ]
   = Rs. (39000 - 34009)
   = Rs. 4991.

Question: 3 -

2 years ago, the average age of a family of 5 members was 16 years. After a baby is born, the average age of family is the same today. Find the present age of the baby.

4 years

8 years 

8 ½ years

6 years

Answer:

6 years

Solution:

(1) First find total age of 5 members 2 years ago (2) Present age of 5 members (3) Total age of 6 members (4) Age of baby = Total age of 6 members - Present age of 5 members

Question: 4 -

In the first 10 overs of a cricket game, the run rate was only 3.2. What should be the run rate in the remaining 40 overs to reach the target of 282 runs? 

7

6.5

6.75

6.25

Answer:

6.25

Solution:

Required run rate =   282 - (3.2 x 10) /40 =  250/40     = 6.25

Question: 5 -

A person covers a distance of 60 km from P to Q at a speed of 20 km/hr and returns from Q to P at a speed of 30 km/hr. Find the average speed of person. 

26 km/hr

28.2 km/hr

24 km/hr

22 km/hr

Answer:

24 km/hr

Solution:

Average Speed =(2 V1 V2)/(V1 + V2)