Question

Twenty students in Class A and 20 students in Class B were asked how many hours they took to prepare for an exam. The data sets represent their answers. Class A: {2, 5, 7, 6, 4, 3, 8, 7, 4, 5, 7, 6, 3, 5, 4, 2, 4, 6, 3, 5} Class B: {3, 7, 6, 4, 3, 2, 4, 5, 6, 7, 2, 2, 2, 3, 4, 5, 2, 2, 5, 6} Which statement is true for the data sets? A. The mean study time of students in Class A is less than students in Class B. B. The mean study time of students in Class B is less than students in Class A. C. The median study time of students in Class B is greater than students in Class A. D. The range of study time of students in Class A is less than students in Class B. E. The mean and median study time of students in Class A and Class B is equal.

Answer 1

Answer:

Option B

Step-by-step explanation:

Given  

Two Data sets

Class A :{ 2, 5, 7, 6, 4, 3, 8, 7, 4, 5, 7, 6, 3, 5, 4, 2, 4, 6, 3, 5}

Class B : {3, 7, 6, 4, 3, 2, 4, 5, 6, 7, 2, 2, 2, 3, 4, 5, 2, 2, 5, 6}

In order to check the options we will have to find the mean and median of both data sets.

So for Class A:

Mean= x =(Sum of values)/(Number of values)

=96/20

=4.8

For median the data has to be arranged in ascending order, so

2, 2,3,3,3,4,4,4,4,5,5,5,5,6,6,6,7,7,7,8

Median will be the average of middle two values as the number of items are odd.

Median=(5+5)/2

=10/2

=5

Range = 8-2 = 6

For Class B:

Mean= x =(Sum of values)/(Number of values)

=80/20

=4

For median, arranging the values

2,2,2,2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,7,7

Median=(4+4)/2

=8/2

=4

Range = 7-2 = 5

We get,

Mean of class A > Mean of Class B

Median of Class A > Median of Class B

Range of Class A > Range of Class B

We observe that only option B is correct for the given data sets..