Given:
n = 20, sample size
xbar = 17.5, sample mean
s = 3.8, sample standard deiation
99% confidence interval
The degrees of freedom is
df = n-1 = 19
We do not know the population standard deviation, so we should determine t* that corresponds to df = 19.
From a one-tailed distribution, 99% CI means using a p-value of 0.005.
Obtain
t* = 2.8609.
The 99% confidence interval is
xbar +/- t*(s/√n)
t*(s/√n) = 2.8609*(3.8/√20) = 2.4309
The 99% confidence interval is
(17.5 - 2.4309, 17.5 + 2.4309) = (15.069, 19.931)
Answer: The 99% confidence interval is (15.07, 19.93)
My guess would be x = -30
Answer:
33
Step-by-step explanation:
33 can be divided evenly by numbers other than one or itself
Using proportions, it is found that the angular velocity at the tip of the blade is of 753.98 radians per minute.
<h3>What is a proportion?</h3>
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
Each revolution has 
radians, hence in one minute, the 120 revolutions will have a measure in radians of:
M = 120 x 2pi = 240pi = 753.98
Hence the angular velocity is of 753.98 radians per minute.
More can be learned about proportions at brainly.com/question/24372153
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