A high school track is shaped as a rectangle with a half circle on either side.
2 answers:
Answer:
1,207.6 m
Step-by-step explanation:
<u><em>The picture of the question in the attached figure</em></u>
we know that
The perimeter of the high school track is equal to the sum of the length of rectangle multiplied by 2 plus the circumference of a circle (remember that the sum of the circumference of two semicircles is equal to the circumference of one circle)
so
we have
substitute
Multiply the perimeter by 4 (because Jake plans on running four laps)
so
You might be interested in
Answer:
The mean is of -0.4 hours.
Step-by-step explanation:
To solve this question, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean and standard deviation
, the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean
and standard deviation
.
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Mean of the sample of 64 Duracell:
By the Central Limit Theorem, 4.1 hours.
Mean of the sample of 64 Eveready:
By the Central Limit Theorem, 4.5 hours.
Mean of the difference?
Subtraction of normal variables, so we subtract the means.
4.1 - 4.5 = -0.4
The mean is of -0.4 hours.
The distance d is 9 ft and the height is 12ft.
<h3>How to find the distance and the height?</h3>
Here we can model the situation with a right triangle, where the length of the wire is the hypotenuse.
The height is one cathetus and the distance is the other catheti.
Let's define:
- h = height
- d = distance.
- hypotenuse = 15ft
We know that the height of the tower is 3 ft larger than the distance, then:
h = d + 3ft
Now we can use the Pythagorean theorem, it says that the sum of the squares of the cathetus is equal to the square of the hypotenuse.
Then:
Now we can solve this equation for d:
Then the solutions are:
We only take the positive solution:
d = (-3ft + 21ft)/2 = 9ft
And the height is 3 ft more than that, so:
h = 9ft + 3ft = 12ft
The distance d is 9 ft and the height is 12ft.
If you want to learn more about right triangles:
#SPJ1