3 (a) In the manufacturing of a certain scientific instrument great importance is attached to the life of a particular critical component. This component is obtained in bulk from two sources, A and B, and in the course of inspection, the lives of 100 of the components from each source are determined. The following tables are obtained: -[3]

Source A

Source B

Log x

No of components

Log x

No of Components

1.7202

1.6990

1.6767

1.6532

1.6284

1.6021

1.5740

1

12

23

20

19

16

9

1.5682

1.6232

1.6721

1.7160

1.7559

1.7924

1.8261

13

15

17

28

12

10

05

Which source is more consist

(b) In the manufacturing of a certain scientific instrument great importance is attached to the life of a particular critical component. This component is obtained in bulk from two sources, A and B, and in the course of inspection, the lives of 1000 of the components from each source are determined. The following frequency tables are obtained: -[3]

Source A

Source B

Life (hours)

No of components

Life(hours)

No of Components

1000-1020

1020-1040

1040-1060

1060-1080

1080-1100

1100-1120

40

x

364

372

85

43

1030-1040

1040-1050

1050-1060

1060-1070

1070-1080

1080-1090

339

136

25

20

130

350

Find missing value of x and Standard deviation, when = 1059.90 for each source and compare them.