Stat 230 Introduction to Statistics Name__

Answer Sheet

Record your answers and work.

Problem Number

Solution

1

(25 pts)

Answers:

(a) True

(b) True

(c) False

(d) True

(e) False

Work for (a), (b), (c), (d) and (e):

2

(5 pts)

Answer: 70%

Work:

Checkout Time

Frequency

(in minutes)

1.0 - 1.9

2

2.0 - 2.9

12

3.0 - 3.9

2

4.0 - 4.9

4

Total

20

percentage of the checkout times was less than 3 minutes 14/20 0.7 70%

3

(5 pts)

Answer: 2nd class: 2.0 - 2.9

Work: Here, n 20,

Median n/2th observation when n even,

Here, n 20/2th obs 10th observation. Thus median is expected to lie in 2nd class which is 2.0 - 2.9.

4

(5 pts)

Answer:

Work:

Checkout Time

Frequency

(in minutes)

fi

mid point (xi(

fixi

1.0 - 1.9...