Number Series Questions

What should come in place of the question mark (?) in the following number series?

8, 6, 9, 23, ?

In the following question, select the missing number from the given series.

964, ?, 241, 120.5, 60.25

In the following question, select the missing number from the given series.

13, 17, 26, 42, 67, ?

In the following question, select the missing number from the given series.

24, 26, 28, ?, 32, 34

In the following question, select the missing number from the given series.

12, 17, 34, ?, 78, 83, 166

In the following question, select the missing number from the given series.

42, 21, 21, ?, 63, 157.5

Next number in the given series is

9 7 10 6 11 ?

In the following question, select the missing number from the given series.

67, 80, 93, ?, 119, 132