A traffic inspector has counted the number of cars passing the traffic light junction of Taman

Sri Pulai Perdana and Taman Teratai, in a time period of 20-minutes for 100 times during

morning peak hours.

The observations are listed below:

TABLE 2: NUMBER OF CARS PASSING TRAFFIC LIGHT JUCTION OF TAMAN

SRI PULAI PERDANA AND TAMAN TERATAI

23 20 16 18 30 22 26 15 5 18

14 17 11 37 21 6 10 20 22 25

19 19 19 20 12 23 24 17 18 16

27 16 28 26 15 29 19 35 20 17

12 30 21 22 20 15 18 16 23 24

15 24 28 19 24 22 17 19 8 18

17 18 23 21 25 19 20 22 21 21

A S S I G N M E N T 1 | v1

2

16 20 19 11 23 17 23 13 17 26

26 14 15 16 27 18 21 24 33 20

21 27 18 22 17 20 14 21 22 19

Construct a histogram (and its cell frequency table) to show the above results.

1. Calculate:

a. range

b. cell interval using Sturgis Rule

c. cell midpoint

d. cell boundaries

2. Indicate the value of following quartile and percentile:

a. Q1 and Q3 of the quartile

b. P20, P58 and P77 of the percentile

3. Find the percentile corresponding to the value:

a. 19.5

b. 8.9

c. 28