6. Look at this series: 21, 9, 21, 11, 21, 13, 21, … What number should come next?

A. 14
B. 15
C. 21
D. 23

7. Look at this series: 58, 52, 46, 40, 34, … What number should come next?

A. 26
B. 28
C. 30
D. 32

8. Look at this series: 3, 4, 7, 8, 11, 12, … What number should come next?

A. 7
B. 10
C. 14
D. 15

9. Look at this series: 8, 22, 8, 28, 8, … What number should come next?

A. 9
B. 29
C. 32
D. 34

10. Look at this series: 31, 29, 24, 22, 17, … What number should come next?

A. 15
B. 14
C. 13
D. 12