What is the 7th term of the geometric sequence where a1 = 128 and a3 = 8?

A.) 0.03125

B.) 0.0625

C.) 0.125

D.) 0.15625

Question

Mathematics

Gia

1 April, 18:28

What is the 7th term of the geometric sequence where a1 = 128 and a3 = 8?

A.) 0.03125

B.) 0.0625

C.) 0.125

D.) 0.15625

+2

Answers (1)

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Francisco Dorsey · Answer 1

An = ar^ (n-1)

a3 = 128r^ (3 - 1) = 128r^2

128r^2 = 8

r^2 = 8/128 = 1/16

r = sqrt (1/16) = 1/4

a7 = 128r^ (7 - 1) = 128r^6 = 128 (1/4) ^6 = 128 (1/4,096) = 0.03125

What is the 7th term of the geometric sequence where a1 = 128 and a3 = 8?A.) 0.03125B.) 0.0625C.) 0.125D.) 0.15625

What is the 7th term of the geometric sequence where a1 = 128 and a3 = 8?

A.) 0.03125

B.) 0.0625

C.) 0.125

D.) 0.15625