Question

Solve the following: S5 for 600 + 300 + 150 + .

Answer 1

600 + 300 + 150 + . . . is a geometric sequence with a = 600 and r = 1/2
Sn = a(1 - r^n)/(1 - r)
S5 = 600(1 - (1/2)^5)/(1 - 1/2) = 600(1 - 1/32)/(1/2) = 1,200(31/32) = 1,162.5