Answer:
179.159
Step-by-step explanation:
Given the sequence :
50, 60, 72,..
The sequence given is a geometric sequence :
For a geometric sequence ;
ar^(n - 1)
a = first term
r = a2 / a1 = 60 / 50 = 1.2
The 8th term ; n =8
a8 = ar^(n - 1)
a8 = 50*1.2^(8 - 1)
a8 = 50*1.2^7
a8 = 50*3.5831808
a8 = 179.15904
a8 = 179.159 (nearest thousandth )
Disclamer: the following is confusing but I will transcribe what is going on in my head
3:4, 3+4=7
4:5, 4+5=9
hm
we can do fractions
3:4, 4 units is yellow
4/7 of all is yellow
4:5, 5/9 of all is yellow
all end is all-9
yellow intial=6+yellowfinal
yellowinitial=(4/7)all
(let's say all=x)
yi=(4/7)x
final=(5/9)(x-9)
yi=6+yf
(4/7)x=6+(5/9)(x-9)
times both sides by 63
36x=378+35(x-9)
distribute
36x=378+35x-315
36x=35x+63
minus 35x both sides
x=63
yellow=(4/7)(x)
yellow=(4/7)(63)
yellow=36
there wer 36 originally
Oops ignore it mate asks else
X is bigger than 65 but smaller or equal to 69. Looks a bit like this...6569.
(However “>“ is a little different as there should be a line under it to show how it can be equal to 69.
Here is the solutions for 3-11