Use the formula of a geometric sequence and find the sum of the first five terms. a1 = -3.449 and r = 1.727

Question

a. 

28.68

b. 

-37.46

c. 

-68.14

d. 

19.76

Answer 1

S_n = a₁(1-rⁿ)/(1-r) where r≠1

S₅ = -3.449(1-1.727⁵)/(1-1.1727) ≈ -68.14

Hope this helped!