Question

If $5^{th}$ and $6^{th}$ term of an $A.P.$ are $6$ and $5$ respectively, then the ${11}^{th}$ term is

• A. $10$
• B. $11$
• C. $0$
• D. $12$

Answer 1

The correct option is C $0$

$T_5=6\Rightarrow a+4d=6.....\left(i\right)T_6=5\Rightarrow a+5d=\mathrm{5.....}\left(ii\right)$

By solving both equations,we get
$a=10,d=-1\Rightarrow T_{11}=a+10d\Rightarrow T_{11}=10-10=0$