Dibuat Diperiksa Mengetahui

Tanggal 4 September 2014 Tanggal 4 September 2014 Tanggal 4 September 2014

Oleh Rini Syahfitri Oleh Rian Kamal Fikri Oleh Akbar Rusavel Nafis

Jabatan Asisten Pembimbing Jabatan Koordinator Praktikum Jabatan Koordinator Asisten

TandaTangan TandaTangan

TandaTangan

DEPARTEMEN PENDIDIKAN NASIONAL

UNIVERSITAS ANDALAS FAKULTAS TEKNIK

JURUSAN TEKNIK INDUSTRI

LABORATORIUM PERENCANAAN DAN OPTIMASI SISTEM INDUSTRI

PRE-TEST

INDUSTRIAL STATISTICS I

DESCRIPTIVE STATISTICS

1. The following measurements were recorded for the drying time, in hours, of certain

brand of latex paint.

3,4 2,8 4,8 2,9 3,6 3,3

4,4 4,0 5,6 3,7 2,8 3,0

Assume the measurements are simple random sample. Calculated the sample mean,

median, and mode.

2. According to the journal Chemical Engineering, an important property of a fiber is

its water absorbency. A random sample of 20 pieces of cotton fiber was taken

and the absorbency on each piece was measured. The following are the

absorbency values:

18.71 21.41 20.72 21.81 19.29 22.43 20.17

23.71 19.44 20.50 18.92 20.33 23.00 22.85

19.25 21.77 22.11 19.77 18.04 21.12

(a) Calculate the sample mean and median for the above sample values.

(b) Find Q1, Q2 and Q3.

3. The lengths of power failures, in minutes, are recorded in the following table.

22 18 135 15 90 78 69 98 102

83 55 28 121 120 13 22 124 112

70 66 74 89 103 24 21 112 21

40 98 87 132 115 21 28 43 37

50 96 118 158 74 78 83 93 95

Dibuat Diperiksa Mengetahui

Tanggal 4 September 2014 Tanggal 4 September 2014 Tanggal 4 September 2014

Oleh Rini Syahfitri Oleh Rian Kamal Fikri Oleh Akbar Rusavel Nafis

Jabatan Asisten Pembimbing Jabatan Koordinator Praktikum Jabatan Koordinator Asisten

TandaTangan TandaTangan

TandaTangan

DEPARTEMEN PENDIDIKAN NASIONAL

UNIVERSITAS ANDALAS FAKULTAS TEKNIK

JURUSAN TEKNIK INDUSTRI

LABORATORIUM PERENCANAAN DAN OPTIMASI SISTEM INDUSTRI

(a) Find the sample mean, sample median and sample mode of the power-

failure times.

(b) Calculate the sample variance and standard deviation of the

power-failure times.