The perimeter of a semicircle consists of two parts. (the curve and bottom)
That curve is half the distance around the circle, since it's been split in half.
The distance around a circle, the circumfrence, is equal to 2πr, where r is the radius of that circle. In this case, the circumfrence of the entire circle would be 16π. and so that curve would have a length of just 8π.
Using 3.14 for π, 8π = 8×3.14 = 25.12.
As for the flat part, that is the diameter (distance across) our circle.
The radius is the distance from the center of a circle to its edge, and always has half the length of the diameter. (you can break the diameter down into two radii)
If our radius is 8 meters, our diameter (the flat part of that semicircle) must be 16.
Now we add up the two parts of the perimeter...25.12 + 16 = 41.12.
Where is the diagram? How do we answer without it?
Answer:
(53.3; 56.1)
Step-by-step explanation:
Given that:
Sample size, n = 41
Mean, xbar = 54.7
Standard deviation, s = 5.3
Confidence level, Zcritical at 90% = 1.645
Confidence interval :
Xbar ± Margin of error
Margin of Error = Zcritical * s/sqrt(n)
Margin of Error = 1.645 * 5.3/sqrt(41)
Margin of Error = 1.362
Lower boundary = 54.7 - 1.362 = 53.338
Upper boundary = 54.7 + 1.362 = 56.062
(53.3 ; 56.1)
Answer:
35
Step-by-step explanation:
Since all the angles are the same in this triangle, all the sides should be the same too.
Hence, 3x - 5 = 4x - 30
5 + -1x = -30
-1x = -35
x = 35
Hope this helped!