Answer:
A 40, 80, 160
Step-by-step explanation:
Given:
2.5, 5, 10, 20, ...
geometric sequence has a constant ratio r and is given by
an=a1r(r)^(n-1)
where
an=nth term
r=common ratio
n=number of term
a1=first term
In given series:
a1=2.5
r= a(n+1)/an
r=5/2.5
r=2
Now computing next term a5
a5=a1(r)^(n-1)
= 2.5(2)^(4)
= 40
a6=a1(r)^(n-1)
= 2.5(2)^(5)
=80
a7=a1(r)^(n-1)
= 2.5(2)^(6)
=160
So the sequence now is 2.5, 5, 10, 20,40, 80, 160!
