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

Given: $T_{n+1}=T_{n-1}+T_n$. If the ${12}^{th}$ term is 144 and the ${14}^{th}$ term is 377. What is the ${15}^{th}$ term?

• A. 502
• B. 401
• C. 610
• D. cannot be determined

Answer 1

The correct option is C 610

$T_{n+1}=T_{n-1}+T_n$.

${14}^{th}$ term $={12}^{th}$ term $+{13}^{th}$ term

$⟹144+{13}^{th}$ term $=377$

$⟹{13}^{th}term=233$

${15}^{th}$ term $={13}^{th}$ term $+{14}^{th}$ term $=233+377=610$