Respuesta :

MathPhys

Answer:

6561 / 128

Step-by-step explanation:

The nth term of a geometric sequence is:

a = a₁ (r)ⁿ⁻¹

The first term is 3, and the fourth term is 81/8.

81/8 = 3 (r)⁴⁻¹

27/8 = r³

r = 3/2

The eighth term is therefore:

a = 3 (3/2)⁸⁻¹

a = 6561 / 128