Question

The final marks in mathematics of 30 students are as follows:

53, 61, 48, 60, 78, 68, 55, 100, 67, 90,
75, 88, 77, 37, 84, 58, 60, 48, 62, 56,
44, 58, 52, 64, 98, 59, 70, 39, 50, 60.
(i) Arrange these marks in ascending order, 30 to 39 one group,40 to 49 second group etc.
Now answer the following:
(ii) What is the highest score?
(iii) What is the lowest score?
(iv) What is the range?
(v) If 40 is the passmark, how many have failed?
(vi) How many have scored 75 or more?
(vii) Which observations between 50 and 60 have not actually appeared?
(viii) How many have scored less than 50?

Answer 1

(i) Arrange marks in ascending order:
$\begin{array}{ccc}\text{Class Marks}& \text{Observations}& \text{Frequency}\\ 30-39& 37,39& 2\\ 40-49& 44,48,48& 3\\ 50-59& 50,52,53,55,56,58,58,59& 8\\ 60-69& 60,60,60,61,62,64,67,68& 8\\ 70-79& 70,75,77,78& 4\\ 80-89& 84,88& 2\\ 90-99& 90,98& 2\\ 100-109& 100& 1\end{array}$

(ii) Highest score = 100
(iii) Lowest score = 37
(iv) Range = Highest score - Lowest score = 100 - 37 = 63
(v) 2
(vi) 8
(vii) 51, 54, 57
(viii) 5