Answer:
The proportion of temperatures that lie within the given limits are 10.24%
Step-by-step explanation:
Solution:-
- Let X be a random variable that denotes the average city temperatures in the month of August.
- The random variable X is normally distributed with parameters:
mean ( u ) = 21.25
standard deviation ( σ ) = 2
- Express the distribution of X:
X ~ Norm ( u , σ^2 )
X ~ Norm ( 21.25 , 2^2 )
- We are to evaluate the proportion of set of temperatures in the month of august that lies between 23.71 degrees Celsius and 26.17 degrees Celsius :
P ( 23.71 < X < 26.17 )
- We will standardize our limits i.e compute the Z-score values:
P ( (x1 - u) / σ < Z < (x2 - u) / σ )
P ( (23.71 - 21.25) / 2 < Z < (26.17 - 21.25) / 2 )
P ( 1.23 < Z < 2.46 ).
- Now use the standard normal distribution tables:
P ( 1.23 < Z < 2.46 ) = 0.1024
- The proportion of temperatures that lie within the given limits are 10.24%
Answer:
Is that the letter (x) or Is that times?
If it is times; then the difference is:
Option "C" -12x2-x-7
Step-by-step explanation:
why, because it is not solvable
Answers:
- a) 693 sq cm (approximate)
- b) 48 sq cm (exact)
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Explanation:
Part (a)
A regular triangular pyramid, aka regular tetrahedron, has all four triangles that are identical copies of one another. They are congruent triangles. This will apply to part (b) as well.
To find the area of one of the triangles, we'll use the formula
A = 0.25*sqrt(3)*x^2
where x is the side length. This formula applies to equilateral triangles only.
In this case, x = 20, so
A = 0.25*sqrt(3)*x^2
A = 0.25*sqrt(3)*20^2
A = 173.20508 approximately
That's the area of one triangle, but there are four total, so the entire area is about 4*173.20508 = 692.82032 which rounds to 693 sq cm.
The units "sq cm" can be written as "cm^2".
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Part (b)
We'll use the same idea as part (a). But the formula to find the area of one triangle is much simpler.
The area of one of the triangles is A = 0.5*base*height = 0.5*6*4 = 12 sq cm.
So the area of all four triangles combined is 4*12 = 48 sq cm
This area is exact.
The area of each 2D flat net corresponds exactly to the surface area of each 3D pyramid. This is because we can cut the figure out and fold along the lines to form the 3D shapes.