Answer:
Perimeter is 17.07
Step-by-step explanation:
We know that DF = EF = 5 cm, since D and E are the midpoints of AC and AB, both of which are 10 cm in length.
We need to use the Pythagorean theorem to get the length of DE.

So the perimeter of DEF is 5 + 5 + 7.07 = 17.07
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:
x = +√30
Step-by-step explanation:
Please write 30 = x squared as 30 = x^2.
If x^2 = 30, there are two solutions: x = +√30 and x = -√30.
Several possible answers are given. x=30−−√ is closest to the correct one, but must be written as x = √30. Please ask someone how to find the "√" operator in Brainly. Or, just write "sqrt( )" instead.
The population in 2040 of the town can be solved using the formula
F = P( 1 -I)^n
Where F is the future population
P is the present population
I is the decline rate
N is the number of years
F = 22,000(1-0.028)^39
<span>F = 7268</span>
The answer is c. Because all you need to know is to find the other leg and find the perimeter of the whole thing.