Answer:
an = 2·2^(n-1)
Step-by-step explanation:
There are simple tests to determine whether a sequence is arithmetic or geometric. The test for an arithmetic sequence is to check to see if the differences between terms are the same. Here the differences are 2, 4, 8, so are not the same.
The test for a geometric sequence is to check to see if the ratios of terms are the same. Here, the ratios are ...
4/2 = 2
8/4 = 2
16/8 = 2
These ratios are all the same (they are "common"), so the sequence is geometric.
The general term of a geometric sequence with first term a1 and common ratio r is ...
an = a1·r^(n-1)
Filling in the values for this sequence, we find the general term to be ...
an = 2·2^(n-1)
Answer:
In 2009
Step-by-step explanation:
If the wren population is going down by 40% each year, that means the following year's population is just 60% of what was in the previous year. This means that what we have to do is multiply the previous year's number by 0.6 to get the current year's population. If we take the data from 2004 as 100%, we have the following numbers:
2004 = 100%
2005 = 60 % (100 * .6)
2006 = 36 % (60 * .6)
2007 = 21.6 % (36 * .6)
2008 = 12.96 % (21.6 * .6)
2009 = 7.776% (12.96 * .6)
This means that 2009 will show that the wren population is less than 10% (7.776%) than what it was in the year 2004.
I hope this helps! :D
Answer:
1
Step-by-step explanation:
you should remove 8 out of 10 then 2 will remain
then add negative 5 to both sides then we will left with -3x = -3
divide -3 on both sides we find x = 1
Answer:
54 = 2 x 27
the cube root of 27 is 3.
the answer is C
Step-by-step explanation:
