Answer:
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.
Step-by-step explanation:
We have that to find our 
level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of 
.
So it is z with a pvalue of 
, so 
Now, find M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 0.181 - 0.0140 = 0.167 cc/m³.
The upper end of the interval is the sample mean added to M. So it is 0.181 + 0.0140 = 0.195 cc/m³.
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.
Answer:
Step-by-step explanation:
<u>Given:</u>
<u>Find z-score:</u>
- z = (x - μ)/σ
- z = (104 - 80)/12 = 2
Percent value corresponding to 2 as per z-table is 0.9772. This is corresponding to 97.72%.
<u>Percentage of students earned more than $104:</u>
Answer:
Step-by-step explanation:
Answer:
600 ft^3
Step-by-step explanation:
R = 25 cm = 0.25 m
α = 2.00 rad /s²
T(heta) = 4 π
ω = T(heta)/ t
ω = α t
α t = 4 π / t
t ² = 2 π
t = √ ( 2π ) = 2.5 s
ω = α t = 2 · 2.5 = 5 rad/s
v = ω r = 5 · 0.25 = 1.25 m/s
(1) a (rad) = ω² r = 25 · 0.25 = 6.25 m/s²
(2) a (rad) = v² / r = ( 1.25 )² / 0.25 = 0.15625 / 0.25 = 6.25 m/s²
