Discussion:
The following table gives the marks (out of a total of 50 ) scored by 30 candidates in an examination :
5 5 7 10 10 11 12 15 16 17 19 19 19 20 20 20 20
21 26 26 27 28 30 30 33 36 37 37 40 45
1. Using class intervals equal to 5 marks, construct a less than cumulative frequency distribution of the above data. Let 5 be the lower limit of the smallest class. Show all workings and formula used.
2. Calculate the RANGE. Show all workings including formula.
3. Calculate the MEAN. Show all workings includng formula.
4. Calculate the MEDIAN. Show all workings including formula.
5. Calculate the MODE. Show all workings including formula.
6. Calculate the standard deviation. Show all workings including formula.
7. Calculate the interquartile range. Show all workings including formula
8. Calculate the 85th percentile.
9. Comment on the skewness of the data.