Question

Select the correct answer.

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

• B. The mean study time of students in Class B is less than students in Class A

Explanation:

Class A:

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

• Number = 20
• Sum = 96
• Mean = 96/20 = 4.8
• Range = 8 - 2 = 6

Class B:

{3, 7, 6, 4, 3, 2, 4, 5, 6, 7, 2, 2, 2, 3, 4, 5, 2, 2, 5, 6}

• Number = 20
• Sum = 80
• Mean = 80/20 = 4
• Range = 7 - 2 = 5

Correct option is B