Chapter 14.3, Problem 7MCQ

To determine

To calculate: The mode of the test scores.

Answer to Problem 7MCQ

The mode of scores is $89.$

Explanation of Solution

Given information:

  

Formula used:

The mode of a set of data is the most frequent value. Some sets of the data have multiple modes and others have no mode.

Calculation:

Consider the data in ascending order,

  $\left\{\begin{array}{l}54,55,62,62,64,65,71,75,76,77,78,\\ 79,80,82,84,85,86,87,88,89,89,89,\\ 90,92,93,93,95,96,98,99\end{array}\right\}$

Now, making the frequency table

Scores	Frequency
54	1
55	1
62	2
64	1
65	1
71	1
75	1
76	1
77	1
78	1
79	1
80	1
82	1
84	1
85	1
86	1
87	1
88	1
89	3
90	1
92	1
93	2
95	1
96	1
98	1
99	1

Re-arranging the data in frequency table

Class Intervals	Frequency
$50-60$	$\left|\right|$
$60-70$	$\left|\right|\left|\right|$
$70-80$	$\bcancel{\left|\right|\left|\right|}\text{ ||}$$$
$80-90$	$\bcancel{\left|\right|\left|\right|}\bcancel{\left|\right|\left|\right|}$
$90-100$	$\bcancel{\left|\right|\left|\right|}\text{ ||}$

The highest repeated score is 89.

Therefore, the mode is 89.