Answer:
⅘×⅛ = 1/10
Step-by-step explanation:
Answer:
a)
And rounded up we have that n=4906
b) For this case since we don't have prior info we need to use as estimatro for the proportion 
And rounded up we have that n=6724
Step-by-step explanation:
We need to remember that the confidence interval for the true proportion is given by :
Part a
The estimated proportion for this case is 
Our interval is at 90% of confidence, and the significance level is given by
and
. The critical values for this case are:
The margin of error for the proportion interval is given by this formula:
(a)
The margin of error desired is given
and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
Replacing we got:
And rounded up we have that n=4906
Part b
For this case since we don't have prior info we need to use as estimatro for the proportion 
And rounded up we have that n=6724
In order to sole the problem you need to create an equation to model what you are trying to do.
You end up with an equation looking like
25000*0.95^t
25000 is the starting value when t=0
95% is the amount remaining after the 5% decay
0.95 is being raised to the power of t to determine how many times it has decayed
When t=3 the equation should be
25000*0.95^3=21434.375
The answer is b because it repeats “2” two times