Question

Find the 7th term of the geometric progression which begins with -6250,1250,-250

Answer 1

a₇ = - 0.4

Explanation:

The n th term of a geometric progression is

`a_(n)` = a₁
`(r)^(n-1)`

where a₁ is the first term and r the common ratio

Here a₁ = - 6250 and r =
`(1250)/(-6250)` = -
`(1)/(5)` , thus

a₇ = - 6250 ×
`(-(1)/(5)) ^(6)`

= - 6250 ×
`(1)/(15625)` = -
`(6250)/(15625)` = - 0.4