10/100=0.1
1/4=0.25
0.1*0.25=0.025
Answer:
CI = 21 ± 0.365
Step-by-step explanation:
The confidence interval is:
CI = x ± SE * CV
where x is the sample mean, SE is the standard error, and CV is the critical value (either t score or z score).
Here, x = 21.
The standard error for a sample mean is:
SE = σ / √n
SE = 3.2 / √510
SE = 0.142
The critical value is looked up in a table or found with a calculator. But first, we must find the alpha level and the critical probability.
α = 1 - 0.99 = 0.01
p* = 1 - (α/2) = 1 - (0.01/2) = 0.995
Using a calculator or a z-score table:
P(x<z) = 0.995
z = 2.576
Therefore:
CI = 21 ± 0.142 × 2.576
CI = 21 ± 0.365
Round as needed.
Y=1/3[-3]-2 I think is the answer
Let's see
Total votes be x
- 45% of x=3600
- 0.45x=3600
- x=3600/0.45
- x=8000
Now total percentage of vote
Not voted=4%
Find not voted
Total voted
This is a parabola, meaning the equation is a quadratic, so it has 2 roots or x-intercepts, keeping in mind that vertex will lie half-way between those intercepts.
so what's the x-value halfway between -3 and 7? yeap, you guessed it, 2.
so the axis of symmetry for this vertical parabola will be at x = 2.