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:
z is 111 degrees
Step-by-step explanation:
69 ° and z is a linear pair, therefore:
69 + z = 180
z = 180 - 69
z= 111
4, there are 4 equal angles
Length x width is the formula.
so 18 x 18 for 7.
22 x 24 for 8.
and 8 would probably be 5 x 5 to equal 20. so the length and width would be 5 and 5 because 20 is the area
This is not answer but Photomath is really helpful and it shows you step by step on how to solve it as well