<em><u>ANSWER</u></em>
My answer is in the photo above
The compressive strength of concrete is being tested by a civil engineer who tests 12 specimens and finds that the sample mean i
1 answer:
Answer:
The 95% confidence interval for mean compressive strength is:
Step-by-step explanation:
We have a sample of n=12 specimens, with sample mean=3259.9 and sample standard deviation = 35.57.
We know the population is normally distributed.
For a 95% confidence interval and df=n-1=11, the t-statistic is t=2.201.
Then, the CI can be expressed as:
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If the soda can is a cylinder, which is most likely, than that means we need to find the height of the cone. The formula for volume of a cylinder is V= пr^2h (look at the pic for clearer formula) and we know the diameter of the soda can is 6, we know the radius is 3 because diameter is a line reaching from one point of the circle to the other. Radius is a line reaching from the center of the circle to the outside as shown in the image. We divide pi (you can put in the calculator 3.14) from 21, then we get 6.688 (if we round up) and then you must look at the formula now
it looks like
6.688=r^2h
that means we must find 3^2
that basically means 3x3 which is 9
then you have to divide that from 6.688
then you get 0.743
that is your height.
now we must find the volume of the cone. The formula for that is
V=пr^2(h/3)
now lets plug in our info
V=(3.14)(9)(0.743/3)
you get 6.999
it looks like
6.688=r^2h
that means we must find 3^2
that basically means 3x3 which is 9
then you have to divide that from 6.688
then you get 0.743
that is your height.
now we must find the volume of the cone. The formula for that is
V=пr^2(h/3)
now lets plug in our info
V=(3.14)(9)(0.743/3)
you get 6.999