What is the fifth term of the geometric sequence 5,15,

405

Step-by-step explanation:

This is a geometric sequence, so we need the common ratio and the first term

To find the common ratio, we take the second term and divide by the first term

15/5 =3

The common ratio is 3

We are multiplying by 3 each time

The first term is 5

The formula is

an = a1 * (r) ^ (n-1)  where n is the term number

We want the 5th term

a5 = 5 * (3) ^ (5-1)

a5 = 5 *3^4

    = 5 *81

    = 405

1) PEMDAS says that parenthesis go first. So we will first solve what's inside of the parenthesis
(3.5 x 10^6)
(3.5 x 1000000)
(3,500,000)

(5 x 10 ^-3)
(5 x 0.001)
(0.005)

2) now we have 3,500,000 x 0.005, and if we multiply that we get 17,500

Therefore, the answer is 17,500