Answer:
You must survey 784 air passengers.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error is:

95% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
Assume that nothing is known about the percentage of passengers who prefer aisle seats.
This means that
, which is when the largest sample size will be needed.
Within 3.5 percentage points of the true population percentage.
We have to find n for which M = 0.035. So






You must survey 784 air passengers.
So the formula for a volume of a sphere is 4/3 times pi times the radius cubed.
step one: 4/3 times 3.14 = 4.18666666667
Step two: then you cube 8.5 and get 592.45
the final answer is 2,480.3906
So you you are trying to find the area of sphere so you would use this formula
A=4•3.14•r^2
And you already know that the radius is 6 so you would go ahead and plug in the numbers
A=4•3.14•4^2
4^2 is 16 so your final equation would be
A=4•3.14•16
And your answer is
=452.39
45% of 40 is 0.45×40=18 girls
if x girls join then 56% of 40+x is 0.56(40+x)=18+x
22.4+0.56x=18+x
put together like terms
4.4=0.44x
<span>x=10 girls joined</span>