Question

find the exact value of the eighth term of the geometric sequence: 648,216,72,24

Answer 1

8th term is 0.30

Step-by-step explanation:

• Step 1: nth term of a GP = a × r^n-1

• Step 2: Find r.

⇒ r = a2/a1 = 216/648 = 1/3

• Step 3: Calculate 8th term. a = 648, r = 1/3 and n = 8

⇒ 8th term =  648 × (1/3)^8-1 = 648 × (1/3)^7 = 648/2187 = 0.30