STATISTICS REVISION QUESTIONS

20 Statistics Practice Questions

Mean Calculation (Direct and Assumed Mean Method)

1. Find the mean of these values: 25, 30, 35, 45, 50, 60, 65, 70.
2. Find the mean of: 12, 15, 18, 20, 22, 25.
3. Calculate the mean of the following data:
   

   Marks	Frequency
   10	2
   20	4
   30	6
   40	3
   50	5

4. (a) Use the assumed mean method to calculate the mean where A = 24.5
   (b) Calculate Median (c) Calculate mode
   

   Class Interval	Frequency
   0 - 9	3
   10 - 19	7
   20 - 29	10
   30 - 39	5
   40 - 49	2

5. Calculate (a) Mean (b) Mode and (c) Median
   

   Class	Frequency
   5 - 14	4
   15 - 24	6
   25 - 34	10
   35 - 44	8
   45 - 54	2

6. (a) Assumed mean is any number you can think of, now this time the assumed mean is 10, calculate the mean using the assumed value given. (b) Why is it important to choose the assumed mean value from the list of class marks?
   (c) Calculate the median and (d) Mode
   

   Score Range	Frequency
   10 - 19	5
   20 - 29	8
   30 - 39	15
   40 - 49	7
   50 - 59	3

7. (a)The mean of the distribution below is 47.45, use it to find the value of X
   (b) Calculate the Median
   (c) Mode

   Age (Years)	Frequency
   20 - 29	3
   30 - 39	6
   40 - 49	X
   50 - 59	4
   60 - 69	2

8. (a)Given the distribution below, use it to draw Histogram and estimate Mode from it
   (b) Draw the frequency distribution curve on the same axis with Histogram above.
   (c) Draw and ogive (Cumulative frequency Curve) and estimate median.
   (d) use the knowledge of statistics estimate the range of Mean.

   Class	Frequency
   100 - 109	6
   110 - 119	10
   120 - 129	15
   130 - 139	9

Median Questions

9. The mean of the numbers 7, 9, 12, 15, Y, 20, 24 is 19, find the value of Y
10. Calculate the mean, mode and median of:

    Score	Frequency
    10	2
    20	6
    30	8
    40	3

11. Calculate the mean, mode and median of:
    

    Class Interval	Frequency
    0 - 10	2
    10 - 20	5
    20 - 30	12
    30 - 40	9
    40 - 50	2

12. Calculate the mean, mode and median of the salary
    

    Salary (Tsh ‘000’)	Frequency
    100 - 199	5
    200 - 299	9
    300 - 399	11
    400 - 499	7

Mode Questions

13. Find the mode of: 7, 9, 12, 12, 15, 18, 20, 24, 24, 24.
14. From the table below, determine the modal class and calculate mode, and calculate the mean, and median of:

    Class	Frequency
    0 - 9	2
    10 - 19	5
    20 - 29	12
    30 - 39	9

15. Calculate the mean, mode and median of:

    Age	Frequency
    15 - 19	3
    20 - 24	8
    25 - 29	11
    30 - 34	6

Histogram, Frequency Curve, and Ogive Questions

16. Using the table below, draw a histogram:

    Marks	Frequency
    0 - 10	4
    10 - 20	6
    20 - 30	9
    30 - 40	7

17. Draw a frequency curve from the above data.
18. Construct a cumulative frequency table from the following data and draw an ogive:

    Class Interval	Frequency
    10 - 20	2
    20 - 30	4
    30 - 40	6
    40 - 50	8

19. From the ogive curve of the above data, estimate the median.
20. Draw both less than and more than ogives on the same axes from this data:

    Marks	Frequency
    0 - 10	2
    10 - 20	5
    20 - 30	7
    30 - 40	6

If you would like to get this and more questions on your mobile phone share this link to friends then after check us on Whatsapp CHECK US ON WHATSAPP