Question

A series is a number series in which the nth term is given by T_(n+1) = T_(n-1) +T_n. Also T₁=1 and T₂=1
The 66${}^{th}$ term of the series - 1,1,2,3,5,8... is:

• A. odd
• B. even
• C. cannot be determined
• D. none of these

Answer 1

The correct option is B even

Observe the pattern. It is a Fibonacci sequence.

1,1,2,3,5,8...

Every 3${}^{rd}$ term is even. Hence a term which is a multiple of 3 will be even. 66 is a multiple of 3. Hence, the 66${}^{th}$ term is even.