Class interval:	0-8	8-16	16-24	24-32	32-40
Frequency:	5	6	4	3	2

Class interval:

0-10

10-12

20-30

30-40

40-50

Frequency:

9

12

15

10

14

Class interval:

0-8

8-16

16-24

24-32

32-40

Frequency:

5

9

10

8

8

Class interval:

10-30

30-50

50-70

70-90

90-110

110-130

Frequency:

5

8

12

20

3

2

Class interval:

25-35

35-45

45-55

55-65

65-75

Frequency:

6

10

8

12

4