Question

Select the number that can replace the question mark (?) in the following series.
99, 82, 63, 50, 35, ?​

Answer 1

Answer:

It should be 9 and then 11.

Step-by-step explanation:

Diffrence between 99 and 82=17

Diffrence between 82 and 63=19

That make a sequence of 17 and 19.

Next up, diffrence between 63 and 50=13

And diffrence between 50 and 35=15

Which makes a sequence of 13 and 15.

So each sequence has diffrence of 2 numbers (from lower to higher number). And those 2 sequences are differentiated by 2 number gap and the series is going backwards so now it should be 9 and 11 sequence turn.

So, the answer is 9.