A) 20
B) 40
C) 60
D) 80
Correct Answer: B
Solution :
(b): \[{{T}_{n}}=2n+5;\,\,{{T}_{1}}=2(1)+5=7\]; \[{{T}_{2}}=2(2)+5=9;\,\,{{T}_{3}}=2(3)+5=11\]; \[{{T}_{4}}=2(4)+5=13\] \[{{S}_{4}}={{T}_{1}}+{{T}_{2}}+{{T}_{3}}+{{T}_{4}}=7+9+11+13=40\].You need to login to perform this action.
You will be redirected in
3 sec