Question

Choose the correct choice in the following and justify:
(ii) ${11}^{th}termoftheA.P-3,\frac{-1}{2},2is$

A) 28
B) 22
C) -38
D) 44

Answer 1

$GiventhatA.P.is-3,\frac{-1}{2},2\dots \dots Firstterma=-3Commondifference,d=a_2-a_1=\left(\frac{-1}{2}\right)-(-3)=\left(\frac{-1}{2}\right)+3=\frac{5}{2}Weknowthat,a_n=a+(n-1)d{a}_{11}=3+(11-1)\left(\frac{5}{2}\right)a_{11}=3+\left(10\right)\left(\frac{5}{2}\right)a_{11}=-3+25a_{11}=22$
Hence, the answer is option B.