Please help me with this question, and show working out.
1 answer:
<h3>Answer: 2072.4 square cm</h3>
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Explanation:
If you used scissors to cut a vertical slice down the lampshade, then it can be unrolled to form a rectangle.
The horizontal portion of this rectangle is the distance around the circle, which is the perimeter of the circle, or the circumference. That's C = 2pi*r. Check out the diagram below to see what I mean.
The diagram shows that the diameter is 20 cm, so the radius is half that at 20/2 = 10 cm.
The circumference is C = 2*pi*r = 2*pi*10 = 20pi cm exactly
The height of the rectangle is the height of the cylinder, which is h = 30 as shown in the diagram.
The area of the rectangle is length*height = (20pi)*(30) = 600pi square cm exactly.
If we were to use something like pi = 3.14, then its approximate area is 600*pi = 600*3.14 = 1884 square cm
Let's bump this up by 10%. To do so, we'll multiply by 1.10
1.10*1884 = 2072.4
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Answer:
The test statistics is
Step-by-step explanation:
From the question we are told that
The data given is
330 620 1870 2410 4620 6396 7822 81028309 12882 14419 16092 18384 20916 23812 25814
The population mean is
The sample size is n = 16
The null hypothesis is
The alternative hypothesis is
The sample mean is mathematically evaluated as
So
=>
The standard deviation is mathematically represented as
So
=>
Generally the test statistic is mathematically represented as
From the z-table the p-value is
From the values obtained we see that
so we fail to reject the null hypothesis
Which implies that the claim of the NarStor is wrong