Answer:
r = C ÷ 2π
Step-by-step explanation:
Given
C = 2πr ( isolate r by dividing both sides by 2π )
C ÷ 2π = r
Answer:
a)
, in which z is related to the confidence level.
b) A sample size of 991 is needed.
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:
In 16% of all homes with a stay-at-home parent, the father is the stay-at-home parent
This means that
a. What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.03 (round up to the next whole number).
This is n for which . So
, in which z is related to the confidence level.
Question b:
99% confidence level,
So , z is the value of Z that has a pvalue of , so .
Rounding up
A sample size of 991 is needed.
X=5/8 or x=-4/3
here is the work if needed...
24x^2+17x-20=0
Step one: Factor left side of equation.
(8x-5)(3x-4)=0
Step two: Set factor equal to 0.
8x-5=0 or 3x-4=0
x=5/8 or x=-4/3