It’s 8cm, please give me brainliest! I need it to get my next rank!
<h2>
Answer with explanation:</h2>
The confidence interval for population mean is given by :-
(1)
, where = sample mean
z* = critical value.
SE = standard error
and , = population standard deviation.
n= sample size.
As per given , we have
n= 15
It is known that ring diameter is normally distributed.
By z-table ,
The critical value for 95% confidence = z*= 1.96
A 99% two-sided confidence interval on the true mean piston diameter :
(using (1))
[Rounded to three decimal places]
∴ A 99% two-sided confidence interval on the true mean piston diameter = (74.020, 74.022)
By z-table ,
The critical value for 95% confidence = z*= 1.96
A 95% lower confidence bound on the true mean piston diameter:
(using (1))
[Rounded to three decimal places]
∴ A 95% lower confidence bound on the true mean piston diameter= 74.020
4x - 2y = 14
y = 0.5x -1
Get just one variable on one side for both equations.
4x - 2y = 14 ⇒ 4x = 2y + 14 ⇒ 4x - 14 = 2y
y = 0.5x - 1 ⇒ x - 2 = 2y
Use the transitive property and then solve for x.
x-2 = 4x-14
12 = 3x
x = 4
<em>Edit: Apprently I didn't use substitution. Oops! Sorry...</em>
Answer:
A=a+b
2h=20+8
2·20.4≈285.6
Step-by-step explanation: