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 =0.5. This is because, the formula that we use will have 
in the expression and that will be maximum only when =0.5. (For any other value of , we will get a value less than 0.25. For example if, is 0.4, then 
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
Answer is: 2x=12, 14, 16, and 18
Answer:
−
6
=
3
7
n
Step-by-step explanation:
Rewrite the equation as
3
7
n
=
−
6
.
3
7
n
=
−
6
Multiply both sides of the equation by
7
3
.
7
3
⋅
3
7
⋅
n
=
7
3
⋅
−
6
Simplify both sides of the equation.
Tap for more steps...
n
=
−
14
Answer:
Each flower is either red or yellow. Each flower is either a tulip or a rose. For these flowers number of tulips:number of roses 6 : 5.
Step-by-step explanation:
The general term of an arithmetic sequence is,
Where , 
= nth term.
= First term
and d = common difference.
The given sequence is: 57, 66, 75, 84, 93, ...
Here = 57,
d = 66 - 57 = 9
We need to find the 250th term. So, n = 250.
Next step is to plug in these values in the above formula. Therefore,
= 57 + 249 * 9
= 57 + 2241
= 2298
Therefore, 250th of this sequence is 2298
Hope this helps you!
