Step-by-step explanation:
5/8 × 6/8= 30/8 => this is the wrong one
it should be 5/8 × 6/8= 30/64.
9/10×3/10= 27/100 => this is the true one
I think it is 55 because 85-30 = 55
Hope this helps! :D
The nth term of the geometric sequence is:
an=ar^(n-1)
where
a=first term
r=common ratio
n=nth term
from the question:
120=ar(3-1)
120=ar^2
a=120/(r^2)....i
also:
76.8=ar^(5-1)
76.8=ar^4
a=76.8/r^4.....i
thus from i and ii
120/r^2=76.8/r^4
from above we can have:
120=76.8/r²
120r²=76.8
r²=76.8/120
r²=0.64
r=√0.64
r=0.8
hence:
a=120/(0.64)=187.5
therefore the formula for the series will be:
an=187.5r^0.8
Answer:
320
80
Step-by-step explanation:
