Answer:
2
Step-by-step explanation:
Big Brain
Answer:
a
Step-by-step explanation:
just plug in
Answer:
A sample of 1068 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:
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
At 95% confidence, how large a sample should be taken to obtain a margin of error of 0.03 for the estimation of a population proportion?
We need a sample of n.
n is found when M = 0.03.
We have no prior estimate of , so we use the worst case scenario, which is 
Then
Rounding up
A sample of 1068 is needed.
(27⁽⁻ˣ⁺³⁾) (9⁽ˣ⁺¹⁾) = 81
Instead of using logarithmic to find x, Notice that 27, 9 and 81 are the perfect powers of 3. Since 27 = 3³, 9 = 3², and 81 = 3⁴, so
(3³⁽⁻ˣ⁺³⁾) (3²⁽ˣ⁺¹⁾) = 3⁴
3³⁽⁻ˣ⁺³⁾⁺²⁽ˣ⁺¹⁾ = 3⁴
If the bases are the same, then cancel it and bring the power as a new base.
3(-x+3) + 2(x+1) = 4
-3x + 9 + 2x + 2 = 4
-x + 11 = 4
-x = 4 - 11
-x = -7
x = 7
