Question

The final marks in mathematics of 30 students are as follows:
$$\begin{array}{cccccccccc}53,& 61,& 48,& 60,& 78,& 68,& 55,& 100,& 67,& 90\\ 75,& 88,& 77,& 37,& 84,& 58,& 60,& 48,& 62& 56\\ 44,& 58,& 52,& 64,& 98,& 59,& 70,& 39,& 50,& 60\end{array}$$
(i) arrange these marks in the 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 rane?
(v) if 40 is the pass mark 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) Arranging in ascending order:
$\begin{array}{ccccccccccc}37,& 39,& 44,& 48,& 48,& 50,& 52,& 53,& 55& 56,& 58,\\ 58,& 59,& 60,& 60,& 60,& 61,& 62,& 64,& 67,& 68,& 70\\ 75,& 77& 78,& 84,& 88,& 90& 98& 100& & & \end{array}\begin{array}{cc}Class& Frequency\\ 30-39& 2\\ 40-49& 3\\ 50-59& 8\\ 60-69& 8\\ 70-79& 4\\ 80-89& 2\\ 90-99& 2\\ 100-109& 1\end{array}$
(ii) Highest score = 100
(iii) Lowest score = 37
(iv) Range = Highest score - Lowest score
= 100 - 37 = 63
(v) If 40 is marks then the number of students who failed = 2
(vi) No. Of students who scored 75 or more = 8
(vii) Between 50 and 60, the scores which are missing 51, 54,57
(viii) Number of students who scored less then 50 = 2 + 3 = 5