We need to find out how many adults must the brand manager survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage.
From the given data we know that our confidence level is 90%. From Standard Normal Table we know that the critical level at 90% confidence level is 1.645. In other words,  .
.
We also know that E=5% or E=0.05
Also, since,  is not given, we will assume that
 is not given, we will assume that  =0.5. This is because, the formula that we use will have
=0.5. This is because, the formula that we use will have  in the expression and that will be maximum only when
 in the expression and that will be maximum only when  =0.5. (For any other value of
=0.5. (For any other value of  , we will get a value less than 0.25. For example if,
, we will get a value less than 0.25. For example if,  is 0.4, then
 is 0.4, then  and thus,
 and thus,  .).
.).
We will now use the formula

We will now substitute all the data that we have and we will get



which can approximated to n=271.
So, the brand manager needs a sample size of 271
 
        
             
        
        
        
Is 172 the area or perimeter.
 
        
             
        
        
        
Answer:
first one: yes
second one: yes
third one: no
fourth one: yes
Step-by-step explanation:
 
        
                    
             
        
        
        
Answer:
9/20
Step-by-step explanation:
45%=45/100
hope this helps
 
        
             
        
        
        
Answer: B. z-311+311=151+311
Step-by-step explanation:
 You do the opposite since you want to get rid of 311