Question

11. Find the missing number in the series given below. 1,1,2,3,5,8,?,21
a.10
b.11
c.12
d.13​

Answer 1

Answer:

b 11

1,1,2,3,5,8,11,21

Answer 2

Answer: option d (13)

Explanation: in the series

1,1,2,3,5,8__21 we need to find the 7th term

Take the the first two terms 1,1 and find its relation with the third term 2 the relation is as follows 1+1=2

Similarly,

Take third and fourth term and find it relation with fifth term i.e 2+3=5

So the pattern that is common here is that the sum of the consecutive terms gives the nest term in the series.

Mathematically,

nth term+(n+1)th term = (n+2)th term

So here 5th term +6th term =7th term

I.e 5+8=13

Hence your answer is 13...hope this helps :)