Question

What is the value of the fourth term in a geometric sequence for which ay =
10 and r = 0.5?

Answer 1

1.25

Explanation:

a = 10 and r = 0.5

The formula for calculating any term in a geometric sequence is a (the first term) times r (the common ratio) raised to the power of n - 1.

In this case n = 4, since we're looking for the fourth term.

so,

Un = ar^n-1

= ar^4-1

= ar^3

U4 = 10 × 0.5^3

= 10 × 0.125

= 1.25