Answer:
The volume of the metal used is 5277.9 cm³.
Step-by-step explanation:
The volume of a cylinder is given by:

Where:
r: is the radius
h: is the height = 50 cm
The volume of metal (
) can be found by subtracting the internal volume (
) from the external volume (
):

The external radius is given by the sum of the internal radius with the tickness:

Hence, the volume is:

Therefore, the volume of the metal used is 5277.9 cm³.
I hope it helps you!
Answer:
7 hours
Step-by-step explanation:
First you subtract 20 from 69, as the starting fee. That leaves you with 49. 49/7 = 7 hours
Answer:


Step-by-step explanation:
Data provided
represent the sample mean in mg per deciliter of cholesterol level
represent the sample standard deviation
sample size
represent the value that we want to test
t would represent the statistic (variable of interest)
represent the p value for the test (variable of interest)
System of hypothesis
We need to conduct a hypothesis in order to check if the mean is higher than 53 mg per deciliter, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
The statistic is given by:
(1)
Calculate the statistic
Replacing into the formula we got:
P-value
We need to find first the degrees of freedom:

The p value for this case since we have a right tailed test is:

Expand (x - 5)^2
(x - 5)^2 = (x - 5)(x - 5)
Multiply all the terms in the first parenthesis to all the terms in the 2nd:
x * x = x^2
x * -5 = -5x
-5 * x = -5x
-5 * -5 = 25
So we have:
x^2 - 5x - 5x + 25
Combine like terms:
x^2 - 10x + 25
Plug it back in:
y = (x - 5)^2 - 2
y = x^2 - 10x + 25 - 2
Combine like terms:
y = x^2 - 10x + 23