Specimen Number

1

2

3

4

5

6

7

8

9

10

Means

(pre-test) (HB)

64

53

38

58

55

51

55

46

56

56

51.1

(post-test) (HB)

87

57

54

56

65

57

67

51

47

65

60.6

Hardness change (HB)

23

4

16

−2

10

6

12

5

−12

9

9.5

Change%

35.94

7.55

42.11

−3.45

18.18

11.76

21.82

10.87

−34.29

16.07

18.59