Question

Select the correct answer.

Answer 1

D. 21/2

Explanation:

We simply have to evaluate the first three terms based on the progression's formula:

t= 1, the first term is 8, as we see:

`8((1)/(4))^(t-1) = 8((1)/(4))^(1-1) = 8 * 1 = 8`

t=2, the second term is 2, as we see:

`8((1)/(4))^(t-1) = 8((1)/(4))^(2-1) = 8 * (1)/(4) = 2`

t=3, the third term is 1/2, as we see:

`8((1)/(4))^(t-1) = 8((1)/(4))^(3-1) = 8 * (1)/(16) = (1)/(2)`

The sum of the first 3 terms is then: 8 + 2 + 1/2 = 10 1/2

Among the answer choices, D. 21/2, which is 10 1/2.