Question

3,5,9,13,21,.....
1) 32
2) 30
3) 29
4) 25​

Answer 1

Answer:

objection c is correct.

please tell me thanks.

Answer 2

Given: A number series-  3, 5, 9, 13, 21,.....

To find: The number that comes after 21

Solution:

On carefully observing the given number series, we find the following pattern:

∵ 5 = 3 + 2

∵ 9 = 5 + 4

∵ 13 = 9 + 4

∵ 21 = 13 + 8

i.e., Every number is the sum of preceeding number and a multiple of 2 which repeats for two consecutive numbers which can be seen for 9 and 13 (4 is repeated).

So, based on this pattern, the next number will be

∴ 21 + 8 = 29

The series will be:  3, 5, 9, 13, 21, 29

Hence, the number after 21 will be 29. (Option C)